Laboratory characterization of measles virus infection in previously vaccinated and unvaccinated individuals

Onward transmission of measles virus among vaccinated cases in a large community outbreak in Auckland, New Zealand, 2019

BACKGROUND

Isolation of cases and quarantining of non-immune contacts are the mainstay of measles outbreak management in elimination settings. Serology testing of exposed contacts may not be feasible in large outbreaks; therefore, vaccination history is used as a proxy for determining immunity to measles and thus prevention of onward virus transmission. This study sought to investigate the risk of measles virus transmission from individuals with a history of one or two doses of measles-containing vaccine (MCV).

METHODS

 Retrospective analysis of data from measles cases reported to Auckland Regional Public Health Service during the 2019 Auckland region measles outbreak. Vaccination history was verified using patient records and the New Zealand National Immunisation Register. Onward transmission was determined through case interviews and assessment of exposed contacts.

RESULTS

 1451 measles cases were assessed as eligible for vaccination at the time of measles outbreak. Of these, 1015 (70.0%) were unvaccinated, 220 (15.2%) had unknown vaccination status, 139 (9.6%) had received only one dose of MCV and 77 (5.3%) had received two doses of the vaccine. Compared to unvaccinated cases, the odds of onward transmission were lower among those with one dose only (OR 0.41, 95% CI: 0.20-0.75) or two doses of MCV (OR 0.44, 95% CI: 0.17-0.95). Median time since vaccination was longer among those with onward transmission compared to those without onward transmission for one and two doses of the vaccine, suggesting a potential effect of waning immunity among this cohort.

CONCLUSION

 These findings support the hypothesis that measles cases with a history of prior vaccination are less likely to transmit the virus to others compared to unvaccinated cases. Such information can be used to support decisions around quarantine requirements for vaccinated contacts in future measles outbreaks.

Measles in Czech population with varying vaccination rates in 2018-2019: clinical and laboratory differences between vaccinated and unvaccinated individuals and their relevance to clinical practice

BACKGROUND AND OBJECTIVES

In a highly vaccinated population, an increasing number of previously vaccinated measles cases can be expected. The aim of this study was to assess the effect of vaccination on the clinical course and immune response in relation to the current measles case definition.

METHODS

The presence of fever, catarrhal symptoms, exanthema and complications, and specific IgM and IgG positivity were assessed in all 230 patients and compared in 193 patients with known vaccination status, divided into measles-containing vaccine (MCV) groups: MCV0 (85 patients), MCV1 (25 patients) and MCV2 (83 patients).

RESULTS

Statistically significant differences between groups were found for catarrhal symptoms. Conjunctivitis and rhinitis were significantly less frequent in the MCV2 group (47% and 54%) compared to MCV0 (80% and 80%), p < 0.001 and p = 0.002 respectively. Typical exanthema was present in 74 (87%) MCV0 and 56 (67%) MCV2 patients, p = 0.005. Complications were most common in the MCV0 group (29%). ECDC clinical case criteria were met in 81 (95%) MCV0, 18 (72%) MCV1 and 59 (71%) MCV2 patients, p < 0.001. IgM were positive in 64 (83%) MCV0, 14 (74%) MCV1 and 36 (67%) MCV2 patients, differences were not statistically significant. There were highly significant differences in IgG between MCV0 and both vaccinated groups (p < 0.001).

CONCLUSIONS

A redefinition of the clinical case classification is essential to better capture modified measles and to raise awareness among healthcare workers of the differences in measles in vaccinated patients.

Avidity maturation of humoral response following primary and booster doses of BNT162b2 mRNA vaccine among nursing home residents and healthcare workers

Infections, despite vaccination, can be clinically consequential for frail nursing home residents (NHR). Poor vaccine-induced antibody quality may add risk for such subsequent infections and more severe disease. We assessed antibody binding avidity, as a surrogate for antibody quality, among NHR and healthcare workers (HCW). We longitudinally sampled 112 NHR and 52 HCWs who received the BNT162b2 mRNA vaccine after each dose up to the Wuhan-BA.4/5-based Omicron bivalent boosters. We quantified anti-spike, anti-receptor binding domain (RBD), and avidity levels to the ancestral Wuhan, Delta, and Omicron BA.1 & 4/5 strains. The primary vaccination series produced substantial anti-spike and RBD levels which were low in avidity against all strains tested. Antibody avidity progressively increased in the 6-8 months that followed. Avidity significantly increased after the 1st booster but not for subsequent boosters. This study underscores the importance of booster vaccination among NHR and HCWs. The 1st booster dose increases avidity, increasing vaccine-induced functional antibody. The higher cross-reactivity of higher avidity antibodies to other SARS-CoV-2 strains should translate to better protection from ever-evolving strains. Higher avidities may help explain how the vaccine's protective effects persist despite waning antibody titers after each vaccine dose.

Interplay of missed opportunity for vaccination and poor response to the vaccine led to measles outbreak in a slum area of Eastern Mumbai, India

In the third week of September 2022, an outbreak of measles was reported from a slum in Eastern Mumbai, India. We sought to investigate whether failure to vaccinate or vaccine failure was the cause. We constructed an epidemic curve, drew a spot map, and calculated the attack rate and case-fatality ratio. We calculated vaccine effectiveness (VE) for one and two doses of measles vaccine in an unmatched case-control study and did stratified analysis by sex, availability of vaccination card, and migrant status. We identified 358 cases and four deaths with a 11.3% attack rate and 1.1% case fatality, both being highest among 0-24-month-old boys. The epidemic curve suggested a propagated mode of spread. The VE for two doses was 64% (95% confidence interval (CI): 23-73%) among under-5-year-old children and 70% (95% CI: 28-88%) among 5-15-year-old children. Failure to vaccinate, consequent to the COVID-19 pandemic, and vaccine hesitancy might have led to the accumulation of susceptible children in the community. Additionally, the occurrence of case-patients among vaccinated suggests reduced VE, which needs further investigation into humoral and cell-mediated immunity as well as contributory factors including nutritional status. Outbreak response immunization to complete immunization of missed and dropout children was carried out to control the outbreak.

Measles IgG Avidity Assay

Measles IgG avidity assays determine the overall strength of molecular binding between measles-specific IgG antibodies and measles virus antigens. Avidity results can distinguish recent from distant measles virus infections. Individuals who are immunologically naïve to measles virus develop low-avidity antibodies upon measles virus infection or first-time vaccination. Within 4-6 months, antibodies mature to high avidity. Measles avidity assays are most useful in the context of measles elimination. In such settings, avidity and epidemiological and clinical information are used to classify measles breakthrough infections for control and surveillance purposes and to assist in case confirmation when other laboratory results are inconclusive or nonexistent. We present a highly accurate end-titer measles avidity assay that delivers results based on IgG quality (avidity) that are independent of IgG concentration.

Neutralizing Antibody Response to Genotypically Diverse Measles Viruses in Clinically Suspected Measles Cases

The neutralizing antibody (Nt-Ab) response to vaccine and wild-type measles viruses (MeV) was studied in suspected measles cases reported during the years 2012-2016. The neutralization activity against MeV A, D4 and D8 genotypes was studied on sera (Panel A; n = 68 (measles-immunized) and Panel B; n = 50 (unvaccinated)) that were either laboratory confirmed or not confirmed by the presence of IgM antibodies. Additionally, the Nt-Ab response in Panel A was measured against the MeV vaccine and four wild-type viruses. Neutralization results were compared using homology modeling and molecular dynamics simulation (MDS) of MeV-hemagglutinin (H) and fusion (F) proteins. Overall, the Nt-Ab titres for MeV-A were found to be significantly lower than MeV-D4 and MeV-D8 viruses for Panel A. No major difference was noted in Nt-Ab titres between MeV-D8 viruses (Jamnagar and New Delhi), whereas MeV-D4 (Sindhudurg and Bagalkot (BGK) viruses) showed significant differences between Nt-Ab titres for Panel B. Interestingly, the substitutions observed in epitopes of H-protein, L249P and G316A are observed to be unique to MeV-BGK. MDS of H-protein revealed significant fluctuations in neutralizing epitopes due to L249P substitution. The majority of the clinically suspected cases showed Nt-Abs to MeV wild-types. Higher IgG antibody avidity and Nt-Ab titres were noted in IgM-negatives than in IgM-positives cases, indicating reinfection or breakthrough. MDS revealed reduced neutralization due to decreased conformational flexibility in the H-epitope.

Causes of a Low Measles Seroprevalence among Young Healthcare Workers in Korea

BACKGROUND

Sporadic measles outbreaks have continued to occur in Korea, mainly in adults in their 20s and 30s, most notably in 2014 and 2019. We here evaluated the possible causes of a low seroprevalance of measles by testing young healthcare workers (HCWs).

MATERIALS AND METHODS

This study was conducted in a 2,743-bed tertiary-care hospital in Seoul between 2020 and 2021. We performed a measles antibody test (chemiluminescence immunoassay), measured the IgM/IgG index ratio, and conducted an avidity test at 1-month after Measles-Mumps-Rubella (MMR) vaccination in HCWs who had been seronegative for measles. Measles vaccination histories were obtained from the national vaccine registry.

RESULTS

Of the 3,173 HCWs newly employed in our hospital during the study period, 54 with a negative measles IgG at commencement were enrolled. Thirty six (67%) of these subjects were female, and the median age was 25 years (interquartile range [IQR]: 24 - 27). Fourty nine (91%) showed seroconversion at 1 month after the first vaccination. Of these individuals, 38 received both measles IgM and IgG test, and all had an IgM/IgG index <1. Of the 49 seroconverters, all HCWs showed a high avidity index. According to the national immunization registry, 45 (83%) received at least 2 doses of an MMR vaccination.

CONCLUSION

Secondary vaccine failure may underlie vaccine failure in young Korean adults. HCWs born after 1985 with a negative measles antibody may need only a single dose booster vaccination rather than a 2-dose vaccination regimen.

Spotting a potential threat: Measles among pediatric solid organ transplantation recipients

BACKGROUND

Low-vaccination rates worldwide have led to the re-emergence of vaccine-preventable infections, including measles. Immunocompromised patients, including pediatric solid organ transplant (SOT) recipients, are at risk for measles because of suboptimal vaccination, reduced or waning vaccine immunity, lifelong immunosuppression, and global re-emergence of measles.

OBJECTIVES

To review published cases of measles in pediatric SOT recipients to heighten awareness of its clinical manifestations, summarize diagnostic and treatment strategies, and identify opportunities to optimize prevention.

METHODS

We conducted a literature review of published natural measles infections in SOT recipients ≤21 years of age, summarizing management and outcomes. We describe measles epidemiology, recommended diagnostics, treatment, and highlight prevention strategies.

RESULTS

There are seven published reports of measles infection in 12 pediatric SOT recipients, the majority of whom were unvaccinated or incompletely vaccinated. Subjects had atypical or severe clinical presentations, including lack of rash and complications, most frequently with encephalitis and pneumonitis, resulting in 33% mortality. Updated recommendations on testing and vaccination are provided. Treatment options beyond supportive care and vitamin A are limited, with no approved antivirals.

CONCLUSION

While measles is infrequently reported in pediatric SOT recipients, morbidity and mortality remain significant. A high index of suspicion is warranted in susceptible SOT recipients with clinically compatible illness or exposure. Providers must recognize this risk, educate families, and be aware of both classic and atypical presentations of measles to rapidly identify, isolate, and diagnose measles in pediatric SOT recipients. Continued efforts to optimize measles vaccination both pre- and post-SOT are warranted.

Measles outbreak in the sanitary area of Guadalajara (Spain): difficulty in microbiological diagnosis in the era of its elimination

INTRODUCTION

In Spain, like in other countries where endemic measles has been eliminated, there is a need for available diagnostic tolos for confirming any cases in order to prevent and control its transmission. We describe the different microbiological tests used for the diagnosis of measles during an outbreak that occurred in 2019 in the province of Guadalajara (Spain).

METHODS

Serological and molecular tests were performed at the Microbiology laboratory of the Guadalajara University Hospital and at the National Center for Microbiology of the Carlos III Health Institute (Majadahonda, Spain). Patient data were obtained from the surveillance system.

RESULTS

A total of 43 patients had a laboratory diagnosis of measles: 29 cases by PCR (pharyngeal exudate or urine) and positive specific IgM, 11 cases by PCR, and 3 cases only by a positive IgM. Genotype D8 was identified in 35 confirmed cases and genotype A in two that were discarded as post-vaccination cases. PCR was positive in the acute sera of 11 out of 14 patients with a negative IgM. Eleven confirmed cases had recieved one or two vaccine doses. Twelve adult patients were hospitalizated, all of them with a diagnostic of hepatitis.

CONCLUSIONS

The combination of molecular tests and the presence of specific IgM is necessary for a correct diagnosis of measles and also to classify patients with a breakthrough infection or vaccine failures (primary or secondary). Genotyping is essential for the correct classification of the patients in the context of a measles elimination program.

Correlating IgG Levels with Neutralising Antibody Levels to Indicate Clinical Protection in Healthcare Workers at Risk during a Measles Outbreak

The rapid transmission of measles poses a great challenge for measles elimination. Thus, rapid testing is required to screen the health status in the population during measles outbreaks. A pseudotype-based virus neutralisation assay was used to measure neutralising antibody titres in serum samples collected from healthcare workers in Sheffield during the measles outbreak in 2016. Vesicular stomatitis virus (VSV) pseudotypes bearing the haemagglutinin and fusion glycoproteins of measles virus (MeV) and carrying a luciferase marker gene were prepared; the neutralising antibody titre was defined as the dilution resulting in 90% reduction in luciferase activity. Spearman’s correlation coefficients between IgG titres and neutralising antibody levels ranged from 0.40 to 0.55 (p < 0.05) or from 0.71 to 0.79 (p < 0.0001) when the IgG titres were obtained using different testing kits. In addition, the currently used vaccine was observed to cross-neutralise most circulating MeV genotypes. However, the percentage of individuals being “well-protected” was lower than 95%, the target rate of vaccination coverage to eliminate measles. These results demonstrate that the level of clinical protection against measles in individuals could be inferred by IgG titre, as long as a precise correlation has been established between IgG testing and neutralisation assay; moreover, maintaining a high vaccination coverage rate is still necessary for measles elimination.

Breakthrough Infections: A Challenge towards Measles Elimination?

Measles is one of the most contagious diseases known to man. Despite the existence of a safe and effective live attenuated vaccine, measles can appear in vaccinated individuals. Paradoxically, breakthrough cases increase as vaccination coverage in the general population rises. In measles endemic areas, breakthrough cases represent less than 10% of total infections, while in areas with high vaccination coverage these are over 10% of the total. Two different vaccination failures have been described: primary vaccination failure, which consists in the complete absence of humoral response and occurs in around 5% of vaccinated individuals; and secondary vaccination failure is due to waning immunity or incomplete immunity and occurs in 2–10% of vaccinees. Vaccination failures are generally associated with lower viral loads and milder disease (modified measles) since vaccination limits the risk of complicated disease. Vaccination failure seems to occur between six and twenty-six years after the last vaccine dose administration. This review summarizes the literature about clinical, serological, epidemiological, and molecular characteristics of measles breakthrough cases and their contribution to virus transmission. In view of the measles elimination goal, the assessment of the potential decline in antibody protection and the targeted implementation of catch-up vaccination are essential.

Diagnostic Significance of Lactate Dehydrogenase in Measles Virus Reinfection Cases

Lactate dehydrogenase (LDH) levels in measles virus (MeV) reinfection cases for the diagnosis of measles have not been extensively studied. Thus, we evaluated the significance of serum LDH in the immune response of patients with MeV reinfection in comparison with those of patients with primary infection. Among 70 patients who tested positive for MeV-RNA, 42 with high MeV-specific IgG avidity (HA) were suspected as cases of reinfection and 28 with low MeV-specific IgG (LA) were suspected as cases of primary infection. The viral loads in the HA group were also lower than those in the LA group (p < 0.001). The titers of MeV-specific IgM and IgG in the HA group were significantly lower and higher, respectively, than those in the LA group (p < 0.001). The total LDH and LDH isozyme levels were elevated in the LA group compared with those in the HA group (p < 0.001). Through receiver operating characteristic curve analyses, we determined that the area under the curve of total LDH level was 0.87 (95% confidence interval 0.74-1.00) and that the discriminatory accuracy was high for total LDH and all isozymes. By stepwise binary logistic regression analysis considering MeV-specific IgG avidity, we developed a model using IgG, IgM, and total LDH as explanatory variables, which was optimal for distinguishing the LA and HA groups (adjusted R² : 0.773, p < 0.001). Thus, the serum LDH level in addition to IgM and IgG may be useful parameters for differentiating MeV reinfection from primary infection. This article is protected by copyright. All rights reserved.

Control of a nosocomial measles outbreak among previously vaccinated adults in a population with high vaccine coverage: Korea, 2019

We describe a measles outbreak among previously vaccinated healthcare workers (HCWs) and inpatients and the control measures implemented at a tertiary care hospital in 2019. Case-patients were laboratory-confirmed measles with throat swabs tested by quantitative polymerase chain reactions (PCR), during April-May 2019. Medical histories and documented immunization records were obtained. We compared attack rates (ARs) among HCWs by occupational subgroup and age and examined the outbreak-associated costs. The index case was not ascertained. Among 26 measles case-patients (22 HCWs, four inpatients) aged 18-28 years, 25 had previously received measles-mumps-rubella (MMR) vaccine (12/26, 46% (two doses); 13/26, 50% (one dose)), and 16 (62%) had positive results of measles IgG prior to measles diagnosis. ARs were higher among HCWs aged < 30 years (1.88%), especially in the subgroup under 25 years of age (2.22%). Control measures included work restrictions for seronegative HCWs (218/2320, 9.4%) in immunity verification, administration of the MMR vaccine (207 HCWs) or intravenous immunoglobulin (2 HCWs and 11 inpatients), enhanced health surveillance of HCWs, and mandatory assessment of patients with measles-like symptoms at the infectious diseases screening units. The hospital spent 90,417,132 Korean won (US $79,733) in response to the outbreak. Measles outbreaks can occur in healthcare settings despite high population immunity, highlighting the importance of stronger vaccination policies, particularly among young HCWs. Moreover, an effective outbreak response comprising immunization activities and enhanced surveillance of HCWs and patients to rapidly detect measles-like symptoms at a prodromal phase is essential to control nosocomial measles outbreaks.

Measles in Vaccinated People: Epidemiology and Challenges in Surveillance and Diagnosis in the Post-Elimination Phase. Spain, 2014-2020

The MMR vaccination program was introduced in Spain in 1981. Consistently high vaccination coverage has led to Spain being declared free of endemic measles transmission since 2014. A few imported and import-related cases were reported during the post-elimination phase (2014 to 2020), with very low incidence: three cases per million of inhabitants a year, 70% in adults. In the post-elimination phase an increasing proportion of measles appeared in two-dose vaccinated individuals (up to 14%), posing a challenge to surveillance and laboratory investigations. Severity and clinical presentation were milder among the vaccinated. The IgM response varied and the viral load decreased, making the virus more difficult to detect. A valid set of samples (serum, urine and throat swab) is strongly recommended for accurate case classification. One third of measles in fully vaccinated people was contracted in healthcare settings, mainly in doctors and nurses, consistent with the important role of high intensity exposure in measles breakthrough cases. Surveillance protocols and laboratory algorithms should be adapted in advanced elimination settings. Reinforcing the immunity of people working in high exposure environments, such as healthcare settings, and implementing additional infection control measures, such as masking and social distancing, are becoming crucial for the global aim of measles eradication.

Update in Pediatric Diagnostic Microbiology

Infants and young children are uniquely susceptible to primary viral and bacterial infections, predisposing them to responses of greater frequency and severity than in adults. Etiologies and manifestations of infections in pediatric patients are often different than those in adults. It can be challenging for clinical laboratories to implement appropriate microbiologic methods for rapid and accurate diagnoses in this population. Laboratorians should be cognizant of the distinctive features of children to provide comprehensive pediatric clinical microbiology services. This article discusses laboratory aspects of several clinically significant pediatric pathogens that cause severe harm to patients and impact public health responses.

Measles outbreak in the sanitary area of Guadalajara (Spain): Difficulty in microbiological diagnosis in the era of its elimination

INTRODUCTION

In Spain, like in other countries where endemic measles has been eliminated, there is a need for available diagnostic tools for confirming any cases in order to prevent and control its transmission. We describe the different microbiological tests used for the diagnosis of measles during an outbreak that occurred in 2019 in the province of Guadalajara (Spain).

METHODS

Serological and molecular tests were performed at the Microbiology laboratory of the Guadalajara University Hospital and at the National Center for Microbiology of the Carlos III Health Institute (Majadahonda, Spain). Patient data were obtained from the surveillance system.

RESULTS

A total of 43 patients had a laboratory diagnosis of measles: 29 cases by PCR (pharyngeal exudate or urine) and positive specific IgM, 11 cases by PCR, and 3 cases only by a positive IgM. Genotype D8 was identified in 35 confirmed cases and genotype A in 2 that were discarded as post-vaccination cases. PCR was positive in the acute sera of 11 out of 14 patients with a negative IgM. Eleven confirmed cases had recieved one or 2 vaccine doses. Twelve adult patients were hospitalizated, all of them with a diagnostic of hepatitis.

CONCLUSIONS

The combination of molecular tests and the presence of specific IgG and IgM are necessary for a correct diagnosis of measles and also to classify patients with a breakthrough infection or vaccine failures (primary or secondary). Genotyping is essential for the correct classification of the patients in the context of a measles elimination program.

Measles infection in persons with secondary vaccine failure, New York City, 2018-19

A large measles outbreak in New York City, which included cases among vaccinated persons and adults presumed to be immune, provided the opportunity to better understand vaccine failure and the potential impact on measles transmission. Immunoglobulin G (IgG) avidity can distinguish primary (low avidity IgG, indicating no evidence of prior immunity) versus secondary vaccine failure (high avidity IgG, indicating prior immune response and waning antibody). Measles IgG avidity was measured on samples from 62 persons: avidity was high in 53 (16 vaccinated and 37 with unknown vaccination history) and low in 9 (1 recently vaccinated and 8 with unknown vaccination history). Secondary transmission from 2 persons with high-avidity IgG results occurred. These findings illustrate that in settings of sustained measles elimination, measles infection and transmission can occur in persons with secondary vaccine failure, underscoring the need to maintain a high index of suspicion for measles during an outbreak despite prior or presumed prior vaccination.

Prevention and Attenuation of Covid-19 with the BNT162b2 and mRNA-1273 Vaccines

BACKGROUND

Information is limited regarding the effectiveness of the two-dose messenger RNA (mRNA) vaccines BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna) in preventing infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and in attenuating coronavirus disease 2019 (Covid-19) when administered in real-world conditions.

METHODS

We conducted a prospective cohort study involving 3975 health care personnel, first responders, and other essential and frontline workers. From December 14, 2020, to April 10, 2021, the participants completed weekly SARS-CoV-2 testing by providing mid-turbinate nasal swabs for qualitative and quantitative reverse-transcriptase-polymerase-chain-reaction (RT-PCR) analysis. The formula for calculating vaccine effectiveness was 100% × (1 - hazard ratio for SARS-CoV-2 infection in vaccinated vs. unvaccinated participants), with adjustments for the propensity to be vaccinated, study site, occupation, and local viral circulation.

RESULTS

SARS-CoV-2 was detected in 204 participants (5%), of whom 5 were fully vaccinated (≥14 days after dose 2), 11 partially vaccinated (≥14 days after dose 1 and <14 days after dose 2), and 156 unvaccinated; the 32 participants with indeterminate vaccination status (<14 days after dose 1) were excluded. Adjusted vaccine effectiveness was 91% (95% confidence interval [CI], 76 to 97) with full vaccination and 81% (95% CI, 64 to 90) with partial vaccination. Among participants with SARS-CoV-2 infection, the mean viral RNA load was 40% lower (95% CI, 16 to 57) in partially or fully vaccinated participants than in unvaccinated participants. In addition, the risk of febrile symptoms was 58% lower (relative risk, 0.42; 95% CI, 0.18 to 0.98) and the duration of illness was shorter, with 2.3 fewer days spent sick in bed (95% CI, 0.8 to 3.7).

CONCLUSIONS

Authorized mRNA vaccines were highly effective among working-age adults in preventing SARS-CoV-2 infection when administered in real-world conditions, and the vaccines attenuated the viral RNA load, risk of febrile symptoms, and duration of illness among those who had breakthrough infection despite vaccination. (Funded by the National Center for Immunization and Respiratory Diseases and the Centers for Disease Control and Prevention.).

Relationship between biochemical markers and measles viral load in patients with immunologically naive cases and secondary vaccine failure: LDH is one of the potential auxiliary indicators for secondary vaccine failure

This study investigated the correlation between biochemical markers and viral load among 38 measles cases, including 15 immunologically naive patients and 23 patients with secondary vaccine failure (SVF). We examined four biochemical markers, namely, aspartate aminotransferase, alanine aminotransferase, C-reactive protein, and lactate dehydrogenase (LDH) and their relationship between virus genome copy numbers in peripheral blood mononuclear cells (PBMCs) and throat swabs as well as the concentration of measles-specific IgG. Although viral genome copies in both clinical specimens showed a significant correlation with specific IgG concentration, they had a higher correlation in PBMCs (Pearson's product-moment correlation coefficient, -0.662; p < .0001) than in throat swabs (Spearman's rank correlation coefficient, -0.443; p = .0078). The viral load in PBMCs also significantly correlated with LDH values (correlation coefficient, 0.360; p = .036). Thus, the serum LDH level might be a potential auxiliary indicator to distinguish immunologically naive patients with measles from those with SVF.

Does influenza vaccination attenuate the severity of breakthrough infections? A narrative review and recommendations for further research

The effect of influenza vaccination on influenza severity remains uncertain. We reviewed the literature for evidence to inform the question of whether influenza illness is less severe among individuals who received influenza vaccination compared with individuals with influenza illness who were unvaccinated prior to their illnesses. We conducted a narrative review to identify published findings comparing severity of influenza outcomes by vaccination status among community-dwelling adults and children ≥ 6 months of age with laboratory-confirmed influenza illness. When at least four effect estimates of the same type (e.g., odds ratio) were available for a specific outcome and age category (children versus adults), data were pooled with meta-analysis to generate a summary effect estimate. We identified 38 published articles reporting ≥ 1 association between influenza vaccination status and one of 21 indicators of severity of influenza illness among individuals with laboratory-confirmed influenza. Study methodologies and effect estimates were highly heterogenous, with only five severity indicators meeting criteria for calculating a combined effect. Among eight studies, influenza vaccination was associated with 26% reduction in odds of ICU admission among adults with influenza-associated hospitalization (OR = 0.74, 95% CI 0.58, 0.93). Among five studies of adults with influenza-associated hospitalization, vaccinated patients had 31% reduced risk of death compared with unvaccinated patients (OR = 0.69, 95% CI 0.52, 0.92). Among four studies of children with influenza virus infection, vaccination was associated with an estimated 45% reduction in the odds of manifesting fever (OR = 0.55, 95% CI 0.42, 0.71). Vaccination was not significantly associated with receiving a clinical diagnosis of pneumonia among adults hospitalized with influenza (OR = 0.92, 95% CI 0.82, 1.04) or with risk of hospitalization following outpatient influenza illness among adults (OR = 0.60, 95% CI 0.28, 1.28). Overall, our findings support the hypothesis that influenza vaccination may attenuate the course of disease among individuals with breakthrough influenza virus infection.

A measles outbreak in Kansai International Airport, Japan, 2016: Analysis of the quantitative difference and infectivity of measles virus between patients who are immunologically naive versus those with secondary vaccine failure

Since the elimination of the measles virus, patients with vaccination records for the measles-containing vaccine have increased in Japan. According to several studies, the transmission risk from previously immunized patients, especially those with secondary vaccine failure (SVF), is lower than that from those with primary measles infections. Immunological features of SVF were identified per specific immunoglobulin G (IgG) induction with high avidity and high plaque reduction neutralization antibody concentration. However, the virological features of SVF have not been well investigated. To examine not only immunological but also virological differences between SVF and immunologically naive patients, throat swabs and blood and urine specimens of 25 patients with confirmed measles infection after an outbreak at the Kansai International Airport in 2016 were analyzed. Patients were categorized as naive (n = 3) or with SVF (n = 22) based on measles-specific IgG antibody concentrations and their avidity. Virus isolation and quantitative real-time polymerase chain reaction were performed to quantify the viral load in clinical specimens and estimate the infectivity in each specimen. The number of viral genome copies in the blood specimens of those with SVF was significantly different and approximately 1 out of 100 of that in immunologically naive patients. However, genome copy numbers in throat swabs and urine specimens were not significantly different between the groups. The virus was isolated only from those in the naive group. Our study indicated low transmission risk of the virus in patients with SVF.

Anthroposophic Medicine: A Short Monograph and Narrative Review-Foundations, Essential Characteristics, Scientific Basis, Safety, Effectiveness and Misconceptions

INTRODUCTION

Anthroposophic medicine is a form of integrative medicine that originated in Europe but is not well known in the US. It is comprehensive and heterogenous in scope and remains provocative and controversial in many academic circles. Assessment of the nature and potential contribution of anthroposophic medicine to whole person care and global health seems appropriate.

METHODS

Because of the heterogenous and multifaceted character of anthroposophic medicine, a narrative review format was chosen. A Health Technology Assessment of anthroposophic medicine in 2006 was reviewed and used as a starting point. A Medline search from 2006 to July 2020 was performed using various search terms and restricted to English. Books, articles, reviews and websites were assessed for clinical relevance and interest to the general reader. Abstracts of German language articles were reviewed when available. Reference lists of articles and the author's personal references were also consulted.

RESULTS

The literature on anthroposophic medicine is vast, providing new ways of thinking, a holistic view of the world, and many integrating concepts useful in medicine. In the last ∼20 years there has been a growing research base and implementation of many anthroposophical concepts in the integrated care of patients. Books and articles relevant to describing the foundations, scientific status, safety, effectiveness and criticisms of anthroposophic medicine are discussed.

DISCUSSION

An objective and comprehensive analysis of anthroposophic medicine finds it provocative, stimulating and potentially fruitful as an integrative system for whole person care, including under-recognized life processes and psychospiritual aspects of human beings. It has a legitimate, new type of scientific status as well as documented safety and effectiveness in some areas of its multimodal approach. Criticisms and controversies of anthroposophic medicine are often a result of lack of familiarity with its methods and approach and/or come from historically fixed ideas of what constitutes legitimate science.

Transmission Network of Measles During the Yamagata Outbreak in Japan, 2017

Background

A measles outbreak involving 60 cases occurred in Yamagata, Japan in 2017. Using two different mathematical models for different datasets, we aimed to estimate measles transmissibility over time and explore any heterogeneous transmission patterns.

Methods

The first model relied on the temporal distribution for date of illness onset for cases, and a generation-dependent model was applied to the data. Another model focused on the transmission network. Using the illness-onset date along with the serial interval and geographical location of exposure, we reconstructed a transmission network with 19 unknown links. We then compared the number of secondary transmissions with and without clinical symptoms or laboratory findings.

Results

Using a generation-dependent model (assuming three generations other than the index case), the reproduction number (R) over generations 0, 1, and 2 were 25.3, 1.3, and <0.1, respectively, explicitly yielding the transmissibility over each generation. The network data enabled us to demonstrate that both the mean and the variance for the number of secondary transmissions per primary case declined over time. Comparing primary cases with and without secondary transmission, high viral shedding was the only significant determinant (P < 0.01).

Conclusions

The R declined abruptly over subsequent generations. Use of network data revealed the distribution of the number of secondary transmissions per primary case and also allowed us to identify possible secondary transmission risk factors. High viral shedding from the throat mucosa was identified as a potential predictor of secondary transmission.

Measles outbreak in Gothenburg urban area, Sweden, 2017 to 2018: low viral load in breakthrough infections

In an outbreak of measles in Gothenburg, Sweden, breakthrough infections (i.e. infections in individuals with a history of vaccination) were common. The objective of this study was to compare measles RNA levels between naïve (i.e. primary) and breakthrough infections. We also propose a fast provisional classification of breakthrough infections. Medical records were reviewed and real-time PCR-positive samples genotyped. Cases were classified as naïve, breakthrough or vaccine infections. We compared clinical symptoms and measles RNA cycle threshold (Ct) values between breakthrough and naïve infections. Sixteen of 28 confirmed cases of measles in this outbreak were breakthrough infections. A fast provisional classification, based on previous history of measles vaccination and detectable levels of measles IgG in acute serum, correctly identified 14 of the 16 breakthrough infections, confirmed by IgG avidity testing. Measles viral load was significantly lower in nasopharyngeal samples from individuals with breakthrough compared with naïve infections (median Ct-values: 32 and 19, respectively, p < 0.0001). No onward transmission from breakthrough infections was identified. Our results indicate that a high risk of onward transmission is limited to naïve infections. We propose a fast provisional classification of breakthrough measles that can guide contact tracing in outbreak settings.

Epidemiology of a workplace measles outbreak dominated by modified measles cases at Kansai international airport, Japan, during august-september 2016

OBJECTIVES

In August 2016, a measles outbreak at Kansai International Airport was the first workplace measles outbreak since Japan was verified as having achieved measles-elimination status in March 2015. We investigated this outbreak with a focus on evaluating the ability of vaccinated individuals to transmit measles virus (MV).

METHODS

We considered a case of laboratory-confirmed measles with onset between August 9 and September 29, 2016, among workers of Kansai International Airport. History of vaccination status with measles-containing vaccine (MCV) was confirmed by reviewing records. The potential sources of each MV infection were assessed by interviewing each infected worker about the clinical course of their infection and their behavioral history.

RESULTS

Of 30 affected ground crews identified, 16 (53%) were vaccinated with ≥ 1 dose of MCV, 2 (7%) were unvaccinated, and 12 (40%) had an unknown vaccination status. The index case, a patient with classical measles with unknown vaccination status, presumably transmitted MV to all the subsequent 29 cases. The majority of patients (23, 77%; 15 vaccinated, 8 in unknown vaccination status) were diagnosed with modified measles due to mild illness. Modified measles were characterized clinically by signs of catarrh (4/23, 17%) in a few cases, with a median incubation period of 16 (range, 11-21) days. No onward transmission from vaccinated cases was suggested. An overseas traveler who visited the airport with measles symptoms was identified as the possible primary source of this outbreak.

CONCLUSIONS

The low MV transmission ability of vaccinated individuals was reaffirmed. Contact tracing of vaccinated modified measles cases can be limited to a person at high risk of infection (e.g., households, person with immunosuppression). To maintain measles-elimination status, completing two doses of MCV should be ensured, especially for international travelers and for those who are frequently exposed to these travelers, such as airport workers.

Evaluating the population measles susceptibility in Tianjin, China

BACKGROUND

Measles is a highly infectious illness requiring herd immunity of 95% to interrupt transmission. China has not reached elimination goals despite high vaccination coverage. We estimated the population susceptibility against measles in Tianjin, China and to tailor awareness raising activities in the measles elimination plan.

METHODS

Age-specific measles seroprevalence was evaluated by Enzyme-Linked Immunosorbent Assay (ELISA) on 12,164 individual aged 0-44 years in 2009-2018. Measles IgG avidity testing was performed to confirm the relationship of the waning immunity after vaccination and secondary vaccination failures (SVF) on 324 confirmed measles cases in 2013-2018.

RESULTS

11,108 samples (91.32%) tested positive for measles IgG, 239 (1.96%) tested as equivocal and 817 (6.72%) were negative. The age distribution of measles cases in Tianjin followed a U-shaped curve and was highest for those at <8 months and again at 20-39 years which correlated closely with the age distribution of measles susceptibility based on measles IgG antibody status (r = 0.72, P < 0.001). The seropositivity rate and antibody geometric mean concentration (GMC) for the 2018 study population were significantly lower (χ² = 7.45, P = 0.006 and t = 12.01, P < 0.001) compared to 2009. The multivariate stepwise logistic regression analysis showed that age and region were the risk factors for both measles seropositivity rate and GMC after vaccination. The proportion of high avidity cases increased with age, being significantly higher in 75.31% of cases in patients aged 30-34 years (χ² = 18.04, P = 0.003).

CONCLUSIONS

High immunization coverage in children alone will not be adequate to realizing sufficient levels of population herd immunity, particularly given that the potential susceptibility window in adult. Implementation of supplemental immunization activity (SIA) targeted to appropriate group aged 30-34 years is recommended.

Qualitative Variation among Commercial Immunoassays for Detection of Measles-Specific IgG

Measurement of measles virus-specific IgG is used to assess presumptive evidence of immunity among immunocompetent individuals with uncertain immune or vaccination status. False-negative test results may lead to unnecessary quarantine and exclusion from activities such as employment, education, and travel or result in unnecessary revaccination. In contrast, false-positive results may fail to identify susceptible individuals and promote spread of disease by those who are exposed and unprotected. To better understand the performance characteristics of tests to detect measles IgG, we compared five widely used, commercially available measles IgG test platforms using a set of 223 well-characterized serum samples. Measles virus neutralizing antibodies were also measured by in vitro plaque reduction neutralization, the gold standard method, and compared to IgG test results. Discrepant results were observed for samples in the low-positive ranges of the most sensitive tests, but there was good agreement across platforms for IgG-negative sera and for samples with intermediate to high levels of IgG. False-negative test results occurred in approximately 11% of sera, which had low levels of neutralizing antibody.

Measles is Back - Considerations for laboratory diagnosis

Measles is a highly contagious viral illness that continues to cause significant mortality among young children worldwide despite the availability of a safe and effective vaccine. During the first half of 2019, over 182 countries reported more than 300,000 measles cases; greater than double the number from the same period in 2018. Timely recognition and laboratory confirmation of infected individuals as well as appropriate infection prevention measures are crucial to avert further transmission. This review highlights the importance of early recognition of the signs and symptoms of measles and provides details on the laboratory methods commonly employed to confirm cases, investigate outbreaks and characterize the virus. It's critical that clinicians, laboratorians and public health administrations work together to rapidly identify, confirm and contain the spread of measles globally.

Recent setbacks in measles elimination: the importance of investing in innovations for immunizations

The recent setbacks in efforts to achieve measles elimination goals are alarming. To reverse the current trends, it is imperative that the global health community urgently intensify efforts and make resource commitments to implement evidence-based elimination strategies fully, including supporting research and innovations. The Immunization Agenda 2030: A Global Strategy to Leave No One Behind (IA2030) is the new global guidance document that builds on lessons learned and progress made toward the GVAP goals, includes research and innovation as a core strategic priority, and identifies measles as a “tracer” for improving immunisation services and strengthening primary health care systems. To achieve vaccination coverage and equity targets that leave no one behind, and accelerate progress toward disease eradication and elimination goals, sustained and predictable investments are needed for the identified research and innovations priorities for the new decade.

Case Report: Diagnosis of COVID-19 versus Tropical Diseases in Pakistan

A 25-year-old medical student presented in Multan, Pakistan with a high fever, cough, myalgia, and diarrhea consistent with the typical signs and symptoms of novel coronavirus disease (COVID-19). The patient had traveled to high COVID-19–risk areas within Pakistan and had no significant medical and surgical history. Based on nasopharyngeal and oropharyngeal swab testing, the patient was found to be negative for COVID-19. He subsequently developed a diffuse rash and had serology consistent with dengue and measles. The patient was treated symptomatically, and his condition gradually improved over 7 days. This case highlights the high prevalence of many tropical diseases in low-income countries and the need for clinicians to consider alternate diagnoses in addition to testing for COVID-19 during the pandemic.

Effect of vaccination on severity and infectiousness of measles during an outbreak in the Netherlands, 2013-2014

An outbreak of measles in the Netherlands in 2013-2014 provided an opportunity to assess the effect of MMR vaccination on severity and infectiousness of measles.Measles is notifiable in the Netherlands. We used information on vaccination, hospitalisation, complications, and most likely source(s) of infection from cases notified during the outbreak. When a case was indicated as a likely source for at least one other notified case, we defined it as infectious. We estimated the age-adjusted effect of vaccination on severity and infectiousness with logistic regression.Of 2676 notified cases, 2539 (94.9%) were unvaccinated, 121 (4.5%) were once-vaccinated and 16 (0.6%) were at least twice-vaccinated; 328 (12.3%) cases were reported to have complications and 172 (6.4%) cases were hospitalised. Measles in twice-vaccinated cases led less often to complications and/or hospitalisation than measles in unvaccinated cases (0% and 14.5%, respectively, aOR 0.1 (95% CI 0-0.89), P = 0.03). Of unvaccinated, once-vaccinated and twice-vaccinated cases, respectively, 194 (7.6%), seven (5.1%) and 0 (0%) were infectious. These differences were not statistically significant (P > 0.05).Our findings suggest a protective effect of vaccination on the occurrence of complications and/or hospitalisation as a result of measles and support the WHO recommendation of a two-dose MMR vaccination schedule.

Measles recognition during measles outbreak at a paediatric university hospital, Austria, January to February 2017

Recognition of measles is crucial to prevent transmissions in the hospital settings. Little is known about the level of recognition of measles and possible causes of not recognising the disease by physicians in the post-vaccine era. We report on a measles outbreak in a paediatric hospital in Austria in January to February 2017 with strikingly high numbers of not recognised cases. The extent and course of the outbreak were assessed via retrospective case finding. Thirteen confirmed measles cases were identified, two with atypical clinical picture. Of eight cases with no known epidemiological link, only one was diagnosed immediately; four were recognised with delay and three only retrospectively. Eleven typical measles cases had four ‘unrecognised visits’ to the outpatient clinic and 28 on the ward. Two atypical cases had two ‘unrecognised visits’ to the outpatient clinic and 19 on the ward.

Thirteen clinicians did not recognise typical measles (atypical cases not included). Twelve of 23 physicians involved had never encountered a patient with measles before. The direct and indirect costs related to the outbreak were calculated to be over EUR 80,000. Our findings suggest the need to establish regular training programmes about measles, including diagnostic pitfalls in paediatric hospitals.

Clinical Characteristics of Measles in Previously Vaccinated and Unvaccinated Patients in California

Background

Measles vaccine failure was first described in 1972. Over the next 20 years, vaccine failure was extensively studied, but during the last 25 years few investigations have been performed. We describe the clinical characteristics of measles in previously vaccinated and unvaccinated patients in California.

Methods

All confirmed measles cases reported to the California Department of Public Health from 1 January 2000 through 31 December 2015 were reviewed. Clinical characteristics (rates of hospitalization, cough, coryza, conjunctivitis, and fever) were compared between the previously unvaccinated, those who had had 1 dose of vaccine, and those who had had ≥2 doses of measles vaccine.

Results

There were 232 confirmed measles cases in whom vaccination status was verified; 80% were unvaccinated, 9% had had 1 dose of measles vaccine, and 11% had had ≥2 doses of measles vaccine. Subjects who had had ≥2 doses of measles vaccine had lower rates of hospitalization, cough, coryza, conjunctivitis, and fever than subjects who had 1 dose of measles vaccine or who were unimmunized.

Conclusions

Vaccine failure measles cases were less ill than cases that occurred in unvaccinated patients. Nevertheless, these cases still required the same amount of public health effort in tracing contacts as in cases who were unvaccinated.

Outbreak of measles among persons with secondary vaccine failure, China, 2018

Although the incidence of measles has been dramatically reduced by the highly effective measles vaccine, cases of measles and outbreaks continue to occur in vaccinated population because of immunization failure. We report on an outbreak in which two cases had previous evidence of measles immunity and then one of them transmitted measles infection to an unvaccinated contact. The cases and contacts exposed during the outbreak were investigated. Clinical information and epidemiological information were obtained. Serum samples were collected for measles-specific immunoglobulin M (IgM), immunoglobulin G (IgG) and IgG avidity. Throat swabs were obtained to test for measles virus RNA. Two measles cases (case 1 and case 2) who have received one dose of MCV in past 5 years, and both working at a hospital in Beijing, occurred in 18th and 20nd of January, respectively. Out of the 102 contacts, one additional case (case 3) who had a close, long-term co-exposure with case 1 was reported subsequently. No additional cases of measles occurred among 15 contacts of case 3. The index case was not ascertained through the outbreak review. All three cases had laboratory confirmation of measles infection. Both case 1 and case 2 had high-avidity IgG antibody characteristic of a secondary immune response and developed a modified clinical presentation. This report confirms that a vaccinated individual with documented secondary vaccine failure (SVF) could transmit measles and is the second report since a New York City outbreak (the first report in China). The outbreak represented a series of rare events, so we can conclude that the SVF individuals in the transmission chain of measles are unlikely to threaten measles elimination. The importance of the herd immunity in preventing transmission and sensitive surveillance activities in case of misdiagnosis is emphasized.

Current perspectives in assessing humoral immunity after measles vaccination

INTRODUCTION

Repeated measles outbreaks in countries with relatively high vaccine coverage are mainly due to failure to vaccinate and importation; however, cases in immunized individuals exist raising questions about suboptimal measles vaccine-induced humoral immunity and/or waning immunity in a low measles-exposure environment.

AREAS COVERED

The plaque reduction neutralization measurement of functional measles-specific antibodies correlates with protection is the gold standard in measles serology, but it does not assess cellular-immune or other parameters that may be associated with durable and/or protective immunity after vaccination. Additional correlates of protection and long-term immunity and new determinants/signatures of vaccine responsiveness such as specific CD46 and IFI44L genetic variants associated with neutralizing antibody titers after measles vaccination are under investigation. Current and future systems biology studies, coupled with new technology/assays and analytical approaches, will lead to an increasingly sophisticated understanding of measles vaccine-induced humoral immunity and will identify 'signatures' of protective and durable immune responses.

EXPERT OPINION

This will translate into the development of highly predictive assays of measles vaccine efficacy, effectiveness, and durability for prospective identification of potential low/non-responders and susceptible individuals who require additional vaccine doses. Such new advances may drive insights into the development of new/improved vaccine formulations and delivery systems.

INFLUENCE OF POPULATION IMMUNITY PECULIARITIES ON THE STRUCTURE OF MEASLES AND RUBELLA PREVALENCE

According to the lasting serological investigations of patients with rubella and measles, a major factor that determines the resistance to the infections is specific antibodies, that are still circulating in blood of recovered persons during their life. Since vaccinated people are also included in this concept, serological monitoring of people different ages who get vaccinated against rubella and measles is conducted in Russia. However the discrepancy between specific immunity intensity and the measles incidence was showed last years. Using “Vector Best” kits, the study of the anti-measles and antirubella population immunity in scale of age: under 1 year, 1–2 years, 3–6 years, 7–14 years, 15–17 years, 18–30 years, 31–40 years, 41–50 years, and 51–60 years was carried out in Moscow and Moscow region in 2013 (period of unfavorable epidemic situation). The serum probes were obtained from 654 random healthy donors and 646 patients with serologically confirmed measles infection. As a result, gradual increase of percentage of people with protective antibodies to rubella and measles have been demonstrated: 81.3% donors aged 7–14 years were protected from measles and more than 90% — from rubella. Moreover, percentage of individuals who have had immunity to rubella were the same in adults too. The most marked increase of percentage of seronegative persons to measles virus (40% and more) was in age from 18 to 30 years, and in groups over the age 40 years old protection reaches 85–95%. Comparison between percentage of measles patients different ages and percentage of persons with protective antibodies in serum have demonstrated significant negative correlation between measles prevalence and the level of specific antibody in population (r = –0.76). According to the results, increase (to 28%) and decrease (to 2.9%) of measles patients aged 18 to 30 and 51 to 60 years are based on decrease (to 55%) and increase (to 95%) of persons with protective immunity, respectively. Results of analysis of measles prevalence in different ages have demonstrated, that among adult measles patients (18–50 years) 14.5% responded on infection by secondary immune response; among children and teenagers there were no such patients, that proves the significant effectiveness of prophylactic vaccines.

High ratio of measles-specific IgG/IgM associated with nodular pneumonia in vaccinated individuals

BACKGROUND

Vaccinated individuals infected with measles can develop nodular pneumonia. These cases can be misdiagnosed due to the absence of specific IgM and typical symptoms. An effective diagnostic tool is needed.

METHODS

During March 2016, adult inpatients in Yucheng People's Hospital were enrolled prospectively and included in the study. Patients were included if samples were obtained ≤14 days from the onset of fever. Measles virus was detected by RT-PCR of the oropharyngeal swab sample. Chest computed tomography scans and medical records were obtained. Oropharyngeal swabs and blood samples were collected for IgM and IgG testing, RT-PCR, and gene sequencing.

RESULTS

Sixteen patients were enrolled. Ten were found to have nodular pneumonia and were defined as the nodular group. The remaining six patients were defined as the control group. Measles-specific IgG titers in the nodular group were high (3618.3-5000mIU/ml), while IgM titers were low (<25mIU/ml); IgG titers in the control group were low (241.4-2560.3mIU/ml), while IgM titers were high (137-5000mIU/ml). No obvious viral mutation was detected in the nodular group.

CONCLUSIONS

Measles-associated nodular pneumonia was only evident in those patients with an IgG/IgM ratio >20. In measles outbreaks, the IgG/IgM ratio may be useful to identify nodular pneumonia.

Detection of modified measles and super-spreader using a real-time reverse transcription PCR in the largest measles outbreak, Yamagata, Japan, 2017 in its elimination era

We aimed to verify the effectiveness of real-time reverse transcription (rRT) polymerase chain reaction (PCR) for detecting cases of modified measles (M-Me) and for predicting super-spreader candidates through the experience of a measles outbreak dominated by M-Me in Yamagata, Japan, during March-April 2017. We applied rRT-PCR to specimens from 35 cases of M-Me, nine cases of typical measles (T-Me) and nine cases of prodromal stage of T-Me (P-Me). From rRT-PCR among the M-Me cases, peripheral blood mononuclear cells (PBMC) showed the highest positive rate (80.0%), followed by throat swab (48.6%), urine (33.3%) and serum (3.1%). The negative result of PBMC in M-Me cases was recovered by the result of a throat swab. In specimens of PBMC, throat swab and urine, M-Me group showed the significantly higher cycle of threshold (i.e., lower viral load) in the rRT-PCR than T-Me and P-Me groups, respectively. Furthermore, three super-spreaders in T-Me or P-Me showed an extremely low cycle of threshold in their throat swab specimens. rRT-PCR using PBMC and throat swab might be helpful for clinical management and measles control by certain detection of M-Me cases and by predicting super-spreading events resulting from measles cases with the high viral load.

Identifying risk factors associated with acquiring measles in an outbreak among age-appropriately vaccinated school children: a cohort analysis

BACKGROUND

A measles outbreak occurred in age-appropriately vaccinated children in a school in a town in the South East of Ireland in September-November 2013.

AIMS

The purpose of this study was to investigate the risk factors associated with catching measles during the outbreak.

METHODS

Ninety-five children (4-5 years) in three classes, in the first year of primary school, were included in the study. Immunisation records on the South East Child Health Information System for first Measles Mumps and Rubella (MMR) vaccine for the 95 children were reviewed. Data collected included age at MMR, date of administration of MMR, MMR brand and batch number, and the General Practice at which MMR was administered. The risk factors analysed included age at vaccination, time of vaccination, class and the GP practice where MMR was administered. Statistical analysis was performed using Epi info 7 and SPSS v24.

RESULTS

Thirteen children in the cohort developed measles during the outbreak. All children in the cohort were age-appropriately vaccinated, with one dose of MMR vaccine. Analysis demonstrated statistically significant differences in the relative risk of developing measles according to the class a child was in, and the General Practice at which they were vaccinated.

CONCLUSIONS

The reason for intense measles activity in one class was not established. Although a concurrent investigation into cold chain and vaccine stock management did not identify a cause for the high relative risk of measles in children vaccinated, recommendations were made for improving cold chain and vaccine stock management in General Practices.

Measles Outbreak in Pediatric Hematology and Oncology Patients in Shanghai, 2015

Background:

Despite substantial progress toward measles control are making in China, measles outbreaks in immunocompromised population still pose a challenge to interrupt endemic transmission. This study aimed to investigate the features of measles in pediatric hematology and oncology patients and explore the reasons behind the outbreak.

Methods:

We collected demographic, epidemiological, and clinical data of immunocompromised measles children. All suspected measles cases were laboratory-confirmed based on the presence of measles IgM and/or identification of measles RNA. The clinical data were statistically analyzed by t-test for continuous variables and Fisher's exact test for categorical variables.

Results:

From March 9 to July 25 in 2015, a total of 23 children with malignancies and post hematopoietic stem cell transplantation (post-HSCT) were notified to develop measles in Shanghai. Of these 23 patients with the median age of 5.5 years (range: 11 months–14 years), 20 (87.0%) had received 1–3 doses of measles vaccine previously; all patients had fever with the median fever duration of 8 days; 21 (91.3%) had cough; 18 (78.3%) had rash; 13 (56.5%) had Koplik's spot; 13 (56.5%) had complications including pneumonia and acute liver failure; and five (21.7%) vaccinated patients died from severe pneumonia or acute liver failure. Except the first patient, all patients had hospital visits within 7–21 days before measles onset and 20 patients were likely to be exposed to each other.

Conclusions:

The outcome of measles outbreak in previously vaccinated oncology and post-HSCT pediatric patients during chemotherapy and immunosuppressant medication was severe. Complete loss of protective immunity induced by measles vaccine during chemotherapy was the potential reason. Improved infection control practice was critical for the prevention of measles in malignancy patients and transplant recipients.

Forgotten but Not Gone: Update on Measles Infection for Hospitalists

Measles (rubeola) continues to be endemic and epidemic in many regions of the world. Measles is primarily a disease of childhood, but it can also affect adult populations, and therefore it is important that both adult and pediatric hospitalist physicians be able to recognize it. Although the disease is rarely encountered in the United States, measles infection can spread rapidly across vulnerable populations. In addition, infected adults can develop complications that may require hospitalization for treatment. This review summarizes the typical clinical course and complications of measles infection, along with recommendations for diagnosis and management for both adult and pediatric hospitalists. Journal of Hospital Medicine 2017;12:472-476.

Measles Outbreak Among Previously Immunized Healthcare Workers, the Netherlands, 2014

BACKGROUND

 We investigated a measles outbreak among healthcare workers (HCWs) by assessing laboratory characteristics, measles vaccine effectiveness, and serological correlates for protection.

METHODS

 Cases were laboratory-confirmed measles in HCWs from hospital X during weeks 12-20 of 2014. We assessed cases' severity and infectiousness by using a questionnaire. We tested cases' sera for measles immunoglobulin M, immunoglobulin G, avidity, and plaque reduction neutralization (PRN). Throat swabs and oral fluid samples were tested by quantitative polymerase chain reaction. We calculated attack rates (ARs) by vaccination status and estimated measles vaccine effectiveness as 1 - [AR_vaccinated/AR_unvaccinated].

RESULTS

 Eight HCWs were notified as measles cases; 6 were vaccinated with measles vaccine twice, 1 was vaccinated once, and 1 was unvaccinated. All 6 twice-vaccinated cases had high avidity and PRN titers. None reported severe measles or onward transmission. Two of 4 investigated twice-vaccinated cases had pre-illness PRN titers of >120 mIU/mL. Among 106 potentially exposed HCWs, the estimated effectiveness of 2 doses of measles vaccine was 52% (95% confidence interval [CI], -207%-93%).

CONCLUSIONS

 Measles occurred in 6 twice-vaccinated HCWs, despite 2 having adequate pre-exposure neutralizing antibodies. None of the twice-vaccinated cases had severe measles, and none had onward transmission, consistent with laboratory findings suggesting a secondary immune response. Improving 2-dose MMR coverage among HCWs would have likely reduced the size of this outbreak.