Associating with kin selects for disease resistance and against tolerance

Behavioural and physiological resistance are key to slowing epidemic spread. We explore the evolutionary and epidemic consequences of their different costs for the evolution of tolerance that trades off with resistance. Behavioural resistance affects social cohesion, with associated group-level costs, while the cost of physiological resistance accrues only to the individual. Further, resistance, and the associated reduction in transmission, benefit susceptible hosts directly, whereas infected hosts only benefit indirectly, by reducing transmission to kin. We therefore model the coevolution of transmission-reducing resistance expressed in susceptible hosts with resistance expressed in infected hosts, as a function of kin association, and analyse the effect on population-level outcomes. Using parameter values for guppies, Poecilia reticulata, and their gyrodactylid parasites, we find that: (1) either susceptible or infected hosts should invest heavily in resistance, but not both; (2) kin association drives investment in physiological resistance more strongly than in behavioural resistance; and (3) even weak levels of kin association can favour altruistic infected hosts that invest heavily in resistance (versus selfish tolerance), eliminating parasites. Overall, our finding that weak kin association affects the coevolution of infected and susceptible investment in both behavioural and physiological resistance suggests that kin selection may affect disease dynamics across systems.

Built Environment and SARS-CoV-2 Transmission in Long-Term Care Facilities: Cross-Sectional Survey and Data Linkage

OBJECTIVES

To describe the built environment in long-term care facilities (LTCF) and its association with introduction and transmission of SARS-CoV-2 infection.

DESIGN

Cross-sectional survey with linkage to routine surveillance data.

SETTING AND PARTICIPANTS

LTCFs in England caring for adults ≥65 years old, participating in the VIVALDI study (ISRCTN14447421) were eligible. Data were included from residents and staff.

METHODS

Cross-sectional survey of the LTCF built environment with linkage to routinely collected asymptomatic and symptomatic SARS-CoV-2 testing and vaccination data between September 1, 2020, and March 31, 2022. We used individual and LTCF level Poisson and Negative Binomial regression models to identify risk factors for 4 outcomes: incidence rate of resident infections and outbreaks, outbreak size, and duration. We considered interactions with variant transmissibility (pre vs post Omicron dominance).

RESULTS

A total of 134 of 151 (88.7%) LTCFs participated in the survey, contributing data for 13,010 residents and 17,766 staff. After adjustment and stratification, outbreak incidence (measuring infection introduction) was only associated with SARS-CoV-2 incidence in the community [incidence rate ratio (IRR) for high vs low incidence, 2.84; 95% CI, 1.85-4.36]. Characteristics of the built environment were associated with transmission outcomes and differed by variant transmissibility. For resident infection incidence, factors included number of storeys (0.64; 0.43-0.97) and bedrooms (1.04; 1.02-1.06), and purpose-built vs converted buildings (1.99; 1.08-3.69). Air quality was associated with outbreak size (dry vs just right 1.46; 1.00-2.13). Funding model (0.99; 0.99-1.00), crowding (0.98; 0.96-0.99), and bedroom temperature (1.15; 1.01-1.32) were associated with outbreak duration.

CONCLUSIONS AND IMPLICATIONS

We describe previously undocumented diversity in LTCF built environments. LTCFs have limited opportunities to prevent SARS-CoV-2 introduction, which was only driven by community incidence. However, adjusting the built environment, for example by isolating infected residents or improving airflow, may reduce transmission, although data quality was limited by subjectivity. Identifying LTCF built environment modifications that prevent infection transmission should be a research priority.

Neurologic Effects of SARS-CoV-2 Transmitted among Dogs

SARS-CoV-2 induces illness and death in humans by causing systemic infections. Evidence suggests that SARS-CoV-2 can induce brain pathology in humans and other hosts. In this study, we used a canine transmission model to examine histopathologic changes in the brains of dogs infected with SARS-CoV-2. We observed substantial brain pathology in SARS-CoV-2-infected dogs, particularly involving blood-brain barrier damage resembling small vessel disease, including changes in tight junction proteins, reduced laminin levels, and decreased pericyte coverage. Furthermore, we detected phosphorylated tau, a marker of neurodegenerative disease, indicating a potential link between SARS-CoV-2-associated small vessel disease and neurodegeneration. Our findings of degenerative changes in the dog brain during SARS-CoV-2 infection emphasize the potential for transmission to other hosts and induction of similar signs and symptoms. The dynamic brain changes in dogs highlight that even asymptomatic individuals infected with SARS-CoV-2 may develop neuropathologic changes in the brain.

Pasteurella Multocida Infection in Humans

Pasteurella multocida (P. multocida) is an immobile, anaerobic, Gram-negative coccobacillus fermenting bacterium. This pathogen is commonly prevalent in the upper airways of healthy pets, such as cats and dogs, but was also confirmed in domestic cattle, rabbits, pigs, birds, and various wild animals. Infection in humans occurs as a result of biting, scratching, or licking by animals and contact with nasopharyngeal secretions. Inflammation at the site of infection develops within the first day from the injury. It is usually confined to the skin and subcutaneous tissue but, in particular situations, may spread to other organs and manifest as a severe systemic infection. Careful history-taking and microbiological confirmation of the infection enable diagnosis and appropriate treatment. Any wound resulting from an animal bite should be disinfected. The preferred and highly effective treatment against local P. multocida infection is penicillin or its derivatives. The prognosis for P. multocida infections depends on the infected site and the patient's comorbidities.

Prevalence of Oral Helicobacter pylori Infection in an Indigenous Community in Southwest Mexico

Purpose

Epidemiological studies have been conducted to improve the health and economic quality of life of indigenous communities in Mexico. These studies have found that infections cause frequent health problems. Helicobacter pylori are responsible for conditions ranging from gastritis to stomach cancer. This study determined the prevalence of H. pylori in families from Siltepec, Chiapas, Mexico.

Patient and Methods

Ninety-nine dental plaque samples from 36 families were studied. Real-time PCR was performed to detect H. pylori using previously reported primers. The Mann-Whitney U-test was used for the statistical analysis. According to the family role of H. pylori-positive individuals, the VacA s1/m1 genotype and CagA gene correlated.

Results

The mother had the highest expression of VacA s1/m1-/cagA- with 19% (8/42), followed by the first child with 14.3% (6/42). The major roles for the vacA s1/m1+/cagA- were the mother and first child with 9.5% (4/42), followed by the remaining children with 4.8% (2/42). The vacA s1/m1-/cagA+ genotype was 7.1% (3/42) for the mother and 4.8% (2/42) for the father. Finally, the vacA s1/m1+/cagA+ genotype only appeared in the mother, son I, and son III with 2.4% (1/42).

Conclusion

The vacA s1/m1/cagA genotypes predominated in the mother, suggesting potential transmission between the mother and child during the first years of life.

Oral transmission of Chagas disease from a One Health approach: A systematic review

OBJECTIVE

To analyse acute Chagas disease (CD) outbreaks through a qualitative systematic review and discuss the determinants for its prevention and control.

METHODS

Review of studies in which clinical cases of oral transmission were confirmed by parasitological and/or serological tests that included an epidemiological investigation of sources of infection, vectors and reservoirs.

RESULTS

Thirty-two outbreaks (1965-2022) were analysed. The main foods involved in oral transmission outbreaks are homemade fruit juices. Different species of vectors were identified. Reservoirs were mainly dogs, rodents and large American opossums (didelphids).

CONCLUSION

Under a One Health approach, environmental changes are one of the factors responsible of the rise of oral transmission of CD. Entomological surveillance of vectors and control of the changes in wild and domestic reservoirs and reinforcement of hygiene measures around food in domestic and commercial sites are needed.

Stenotrophomonas maltophilia natural history and evolution in the airways of adults with cystic fibrosis

Introduction

Stenotrophomonas maltophilia is an opportunistic pathogen infecting persons with cystic fibrosis (pwCF) and portends a worse prognosis. Studies of S. maltophilia infection dynamics have been limited by cohort size and follow-up. We investigated the natural history, transmission potential, and evolution of S. maltophilia in a large Canadian cohort of 321 pwCF over a 37-year period.

Methods

One-hundred sixty-two isolates from 74 pwCF (23%) were typed by pulsed-field gel electrophoresis, and shared pulsotypes underwent whole-genome sequencing.

Results

S. maltophilia was recovered at least once in 82 pwCF (25.5%). Sixty-four pwCF were infected by unique pulsotypes, but shared pulsotypes were observed between 10 pwCF. In chronic carriage, longer time periods between positive sputum cultures increased the likelihood that subsequent isolates were unrelated. Isolates from individual pwCF were largely clonal, with differences in gene content being the primary source of genetic diversity objectified by gene content differences. Disproportionate progression of CF lung disease was not observed amongst those infected with multiple strains over time (versus a single) or amongst those with shared clones (versus strains only infecting one patient). We did not observe evidence of patient-to-patient transmission despite relatedness between isolates. Twenty-four genes with ≥ 2 mutations accumulated over time were identified across 42 sequenced isolates from all 11 pwCF with ≥ 2 sequenced isolates, suggesting a potential role for these genes in adaptation of S. maltophilia to the CF lung.

Discussion

Genomic analyses suggested common, indirect sources as the origins of S. maltophilia infections in the clinic population. The information derived from a genomics-based understanding of the natural history of S. maltophilia infection within CF provides unique insight into its potential for in-host evolution.

Transmission routes and patterns of helicobacter pylori

BACKGROUND AND OBJECTIVE

Helicobacter pylori (H. pylori), a gram-negative bacterium that colonizes the stomach, can cause chronic gastritis and peptic ulcers, as well as gastric cancer as a Class I carcinogen. However, the modes of H. pylori transmission are not clear. This review aims to clarify the transmission routes and patterns of H. pylori and identify efficacious prevention measures.

METHODS

Studies of H. pylori transmission were identified using PubMed, the Web of Science, and Cochrane Central; the retrieval deadline was October 2022.

RESULTS

The transmission routes of H. pylori are discussed, focusing on the five primary transmission routes, namely fecal-oral, oral-oral, gastric-oral, anal-oral, and genital-oral. We propose that H. pylori is contracted through multiple transmission routes. Additionally, we summarize the key transmission patterns of H. pylori, including person-to-person and animal-to-human transmission, as well as foodborne and occupational exposure.

CONCLUSION

Fecal-oral appears to be the most common H. pylori transmission routes. Although the oral-oral pathway is also important, the evidence does not support that this route of transmission is universal. The gastric-oral route occurs primarily in children and patients who are prone to vomiting. Meanwhile, the anal-oral and genital-oral routes remain hypothetical. Person-to-person and foodborne infections represent the predominant transmission patterns of H. pylori, whereas strong environmental and occupational limitations are associated with animal-to-human and occupational exposure.

Investigating dilution ventilation control strategies in a modern U.S. school bus in the context of the COVID-19 pandemic

Fresh air ventilation has been identified as a widely accepted engineering control effective at diluting air contaminants in enclosed environments. The goal of this study was to evaluate the effects of selected ventilation measures on air change rates in school buses. Air changes per hour (ACH) of outside air were measured using a well-established carbon dioxide (CO₂) tracer gas decay method. Ventilation was assessed while stationary and while traversing standardized route during late autumn/winter months in Colorado. Seven CO₂ sensors located at the driver's seat and at passenger seats in the front, middle, and rear of the bus yielded similar and consistent measurements. Buses exhibited little air exchange in the absence of ventilation (ACH = 0.13 when stationary; ACH = 1.85 when mobile). Operating the windshield defroster to introduce fresh outside air increased ACH by approximately 0.5-1 ACH during mobile and stationary phases. During the mobile phase (average speed of 23 miles per hour (mph)), the combination of the defroster and two open ceiling hatches (with a powered fan on the rear hatch) yielded an ACH of approximately 9.3 ACH. A mobile phase ACH of 12.4 was achieved by the combination of the defroster, ceiling hatches, and six passenger windows open 2 inches in the middle area of the bus. A maximum mobile phase ACH of 22.1 was observed by using the defroster, open ceiling hatches, driver window open 4 inches, and every other passenger window open 2 inches. For reference, ACHs recommended in patient care settings where patients are being treated for airborne infectious diseases range from 6 to ≥12 ACHs. The results indicate that practical ventilation protocols on school buses can achieve air change rates thought to be capable of reducing airborne viral transmission to the bus driver and student passengers during the COVID-19 pandemic.

Novel measurement system for respiratory aerosols and droplets in indoor environments

The SARS-CoV-2 pandemic has created a great demand for a better understanding of the spread of viruses in indoor environments. A novel measurement system consisting of one portable aerosol-emitting mannequin (emitter) and a number of portable aerosol-absorbing mannequins (recipients) was developed that can measure the spread of aerosols and droplets that potentially contain infectious viruses. The emission of the virus from a human is simulated by using tracer particles solved in water. The recipients inhale the aerosols and droplets and quantify the level of solved tracer particles in their artificial lungs simultaneously over time. The mobile system can be arranged in a large variety of spreading scenarios in indoor environments and allows for quantification of the infection probability due to airborne virus spreading. This study shows the accuracy of the new measurement system and its ability to compare aerosol reduction measures such as regular ventilation or the use of a room air purifier.

Socioeconomic Patterns of COVID-19 Clusters in Low-Incidence City, Hong Kong

Although coronavirus disease (COVID-19) outbreaks have been relatively well controlled in Hong Kong, containment remains challenging among socioeconomically disadvantaged persons. They are at higher risk for widespread COVID-19 transmission through sizable clustering, probably because of exposure to social settings in which existing mitigation policies had differential socioeconomic effects.

Attempted Control of Paratuberculosis in Dairy Calves by Only Changing the Quality of Milk Fed to Calves

One of the important routes of Mycobacterium avium subsp. paratuberculosis (MAP) transmission in dairy calves is milk. The aim of the present study was to assess the efficacy of milk treatments to prevent MAP infection transmission to calves. A one-year longitudinal study was carried out. Newborn calves were assigned to one of four experimental groups: 5 calves received naturally MAP-contaminated milk, 5 calves received copper treated milk, 4 calves were fed calf milk replacer, and 3 were fed UHT pasteurized milk. MAP load in milk was estimated. Infection progression was monitored monthly. After one year, calves were euthanized, and tissue samples were cultured and visually examined. MAP was undetectable in milk replacer and UHT milk. Copper ion treatment significantly reduced the number of viable MAP in naturally contaminated milk. Fecal shedding of MAP was observed in all study groups but began earlier in calves fed naturally contaminated milk. Paratuberculosis control programs must place multiple hurdles between the infection source, MAP-infected adult cows, and the most susceptible animals on the farm, young calves. As our study shows, strict dependence on a single intervention to block infection transmission, no matter how important, fails to control this insidious infection on dairy farms.

In Situ Measurement of Airborne Particle Concentration in a Real Dental Office: Implications for Disease Transmission

Aerosols generated during dental procedures are one of the most significant routes for infection transmission and are particularly relevant now in the context of COVID-19 pandemic. This study aimed to assess the effectiveness of an indoor air purifier on dental aerosol dispersion in dental offices. The spread and removal of aerosol particles generated from a specific dental operation in a dental office are quantified for a single dental activity in the area near the generation and corner of the office. The effects of the air purifier, door condition, and particle sizes on the spread and removal of particles were investigated. The results show that, in the worst-case scenario, it takes 95 min for 0.5-μm particles to settle and that it takes a shorter time for the larger particles. The air purifier expedited the removal time at least 6.3 times faster than the case with no air purifier in the generation zone. Our results also indicate that particles may be transported from the source to the rest of the room even when the particle concentrations in the generation zone dropped back to the background. Therefore, it is inaccurate to conclude that indoor purifiers help reduce the transmission of COVID-19. Dental offices still need other methods to reduce the transmission of viruses.

SARS-CoV-2 screening: effectiveness and risk of increasing transmission

Testing asymptomatic people for SARS-CoV-2 aims to reduce COVID-19 transmission. Screening programmes’ effectiveness depends upon testing strategy, sample handling logistics, test sensitivity and individual behaviour, in addition to dynamics of viral transmission. The interaction between these factors is not fully characterized. We investigated the interaction between these factors to determine how to optimize reduction of transmission. We estimate that under idealistic assumptions 70% of transmission may be averted, but under realistic assumptions only 7% may be averted. We show that programmes that overwhelm laboratory capacity or reduce isolation of those with minor symptoms have increased transmission compared with those that do not: programmes need to be designed to avoid these issues, or they will be ineffective or even counter-productive. Our model allows optimal selection of whom to test, quantifies the balance between accuracy and timeliness, and quantifies potential impacts of behavioural interventions. We anticipate our model can be used to understand optimal screening strategies for other infectious diseases with substantially different dynamics.

New formulas to predict the length of a peripherally inserted central catheter based on anteroposterior chest radiographs

PURPOSE

To develop formulas that predict the optimal length of a peripherally inserted central catheter (PICC) from variables measured on anteroposterior (AP) chest radiography (CXR).

MATERIALS AND METHODS

A total of 134 patients who underwent PICC insertion at the angiography suites were included. Clinical information such as patient height, weight, sex, age, cubital crease to inferior carina border length (CCL), and approach side were recorded. The following variables via measurement on AP-CXR were also collected: (1) distance from the T1 to T12 vertebra (DTV), (2) maximal horizontal thoracic diameter (MHTD), and (3) clavicle length (CL).

RESULTS

Significant correlations between CCL and the following variables were identified in linear regression analyses: approach side, height, weight, sex, DTV, MHTD, and CL. Multiple regression results motivated the following two formulas: (1) with height data, estimated CCL (cm) = 12.429 + 0.113 × Height + 0.377 × MHTD (if left side, add 2.933 cm, if female, subtract 0.723 cm); (2) without height data, estimated CCL = 19.409 + 0.424 × MHTD + 0.287 × CL + 0.203 × DTV (if left side, add 3.063 cm, if female, subtract 0.997 cm). Estimated final PICC length can be calculated as (Estimated CCL, cm) + 4.0 (distance from inferior carina border to about 2.0 vertebra body unit, cm) - (distance from set cubital crease to designated puncture point, cm).

CONCLUSION

This study suggests new formulas to predict the appropriate PICC length for bedside insertion using previous AP-CXRs. With this formula, ideal positioning of the catheter's tip can be achieved in the clinical practice, avoiding or minimalizing the exposed catheter out of skin. These formulas may be helpful for patients who cannot undergo intra-hospital transport due to hemodynamic instability or who are concerned about isolation precautions due to any infectious-related contamination.

Mycobacterium tuberculosis Beijing Lineage and Risk for Tuberculosis in Child Household Contacts, Peru

Few studies have prospectively compared the relative transmissibility and propensity to cause disease of Mycobacterium tuberculosis Beijing strains with other human-adapted strains of the M. tuberculosis complex. We assessed the effect of Beijing strains on the risk for M. tuberculosis infection and disease progression in 9,151 household contacts of 2,223 culture-positive pulmonary tuberculosis (TB) patients in Lima, Peru. Child contacts exposed to Beijing strains were more likely than child contacts exposed to non-Beijing strains to be infected at baseline, by 12 months of follow-up, and during follow-up. We noted an increased but nonsignificant tendency for child contacts to develop TB. Beijing strains were not associated with TB in adult contacts. These findings suggest that Beijing strains are more transmissible in children than are non-Beijing strains.

A pilot study investigating the social contact patterns of Korean elderly

OBJECTIVES

This pilot study describes the characteristics of social contact patterns of the elderly, a group at high-risk for contracting infections.

DESIGN

A cross-sectional design was used.

SAMPLE

Participants included 30 volunteers aged 65 years or older.

MEASUREMENTS

Records of a contact diary were maintained for a period of 24-hr.

RESULTS

Thirty participants recorded 340 contacts within the 24 hr period, with a mean of 11.3 people daily. Physical encounters accounted for 50.9% of contacts. Participants with an occupation had significantly higher contacts than those without (p=.013). Contact type differed by location and duration (p<.001). Contact locations included: home (11.5%), work (2.4%), elderly welfare facilities (32.9%), transport (1.2%), and other places (52.1%). Contact duration (p < .001) and frequency (p < .001) differed by location. Contact duration differed by frequency (p < .001).

CONCLUSIONS

The elderly participate in frequent physical contact that increases their risk of infection, especially among those with an occupation in comparison to those without an occupation. Infection control nursing should focus on providing education to reduce the risk of infections during contact events. Social distancing should be applied to limited periods of infection transmission risk.

Effect of Acute Illness on Contact Patterns, Malawi, 2017

The way persons interact when ill could profoundly affect transmission of infectious agents. To obtain data on these patterns in Africa, we recorded self-reported named contacts and opportunities for casual contact in rural northern Malawi. We interviewed 384 patients and 257 caregivers about contacts over three 24-hour periods: day of the clinic visit for acute illness, the next day, and 2 weeks later when well. For participants of all ages, the number of adult contacts and the proportion using public transportation was higher on the day of the clinic visit than later when well. Compared with the day after the clinic visit, well participants (2 weeks later) named a mean of 0.4 extra contacts; the increase was larger for indoor or prolonged contacts. When well, participants were more likely to visit other houses and congregate settings. When ill, they had more visitors at home. These findings could help refine models of infection spread.

Altitude and SARS-CoV-2 Infection in the First Pandemic Wave in Spain

After the first pandemic wave, a nationwide survey assessed the seroprevalence of SARS-CoV-2 antibodies in Spain and found notable differences among provinces whose causes remained unclear. This ecological study aimed to analyze the association between environmental and demographic factors and SARS-CoV-2 infection by province. The seroprevalence of SARS-CoV-2 antibodies by province was obtained from a nationwide representative survey performed in June 2020, after the first pandemic wave in Spain. Linear regression was used in the analysis. The seroprevalence of SARS-CoV-2 antibodies of the 50 provinces ranged from 0.2% to 13.6%. The altitude, which ranged from 5 to 1131 m, explained nearly half of differences in seroprevalence (R² = 0.47, p < 0.001). The seroprevalence in people residing in provinces above the median altitude (215 m) was three-fold higher (6.5% vs. 2.1%, p < 0.001). In the multivariate linear regression, the addition of population density significantly improved the predictive value of the altitude (R² = 0.55, p < 0.001). Every 100 m of altitude increase and 100 inhabitants/km² of increase in population density, the seroprevalence rose 0.84 and 0.63 percentage points, respectively. Environmental conditions related to higher altitude in winter–spring, such as lower temperatures and absolute humidity, may be relevant to SARS-CoV-2 transmission. Places with such adverse conditions may require additional efforts for pandemic control.

The Impact of SARS-CoV-2 Outbreak on the Polish Dental Community's Standards of Care-A Six-Month Retrospective Survey-Based Study

Currently, SARS-CoV-2 is the primary pathogen worldwide, disrupting most of our everyday activities. The study aim was to evaluate its impact on the Polish dental community, standards of care, health, and welfare. Methods: A Google Forms survey was conducted among 303 dental practitioners. Results: Of respondents, 54.93% curbed the number of patients in the last six months, 34.21% declared no changes, and 10.86% reported an increase; whereas 70.7% of the respondents reported a treatment price increase within the same period (27.96% and 1.32% reported no changes and a decrease, respectively). Of the respondents, 15.5% did not close their businesses during the first wave of the pandemic. Most declared 1 or 2 month break, 30.7% and 34.7%, respectively. Some reported 3, 4, or 5 month breaks (15.84%, 1.32%, and 0.99%, respectively), and only two respondents (0.66%) did not admit patients at all. Headache episodes were more frequent among female dentists before the pandemic; after the pandemic, headache frequency increased among both sexes. Temporomandibular disorders (TMDs) were more frequent among women (p = 0.017). Conclusions: Most Polish dentists followed SARS-CoV-2 recommendations and restricted their practices to admitting only patients with pain or incomplete treatment. Decreased sleep parameters, head, back, and neck pain, were observed. This situation may affect dental health conditions in Polish society over time.

Population Movement, City Closure in Wuhan, and Geographical Expansion of the COVID-19 Infection in China in January 2020

Background

The unprecedented outbreak of 2019-nCoV pneumonia infection in Wuhan City caused global concern, the outflowing population from Wuhan was believed to be a main reason for the rapid and large-scale spread of the disease, so the government implemented a city closure measure to prevent its transmission considering the large amount of travelling before the Chinese New Year.

Methods

Based on the daily reported new cases and the population movement data between January 1 and 31, we examined the effects of population outflow from Wuhan on the geographical expansion of the infection in other provinces and cities of China, as well as the impacts of the city closure in Wuhan in different scenarios of closing dates.

Results

We observed a significantly positive association between population movement and the number of the 2019-nCoV cases. The spatial distribution of cases per unit outflow population indicated that some areas with large outflow population might have been underestimated for the infection, such as Henan and Hunan provinces. Further analysis revealed that if the city closure policy was implemented two days earlier, 1420 (95% CI: 1059, 1833) cases could have been prevented, and if two days later, 1462 (95% CI: 1090, 1886) more cases would be possible.

Conclusions

Our findings suggest that population movement might be one important trigger for the transmission of 2019-nCoV infection in China, and the policy of city closure is effective to control the epidemic.

First report in Japan of a delivery of a woman with the 2019 novel coronavirus disease

On April 2, 2020, we received a maternal transport from a local city hospital of a pregnant woman (38 weeks and 0 days of gestation) in her 20s, who had the 2019 novel coronavirus disease (COVID‐19). We performed an emergency cesarean section with spinal anesthesia because of an abnormal fetal heart rate pattern. A healthy 3106‐g male baby was delivered. All the severe acute respiratory syndrome coronavirus 2 polymerase chain reaction tests of nasal and oral discharges, anal swabs and blood samples of the neonate at 9 h, 30 h and 4 days after birth were negative. Because the mother was diagnosed as having COVID‐19 pneumonia, the neonate was given formula milk. The mother's nasal discharge samples at 20 and 21 days were negative. The mother first held her baby in her arms on the 22nd day after birth, and they were discharged on the following day. To the best of our knowledge, this is the first report in Japan of a delivery of a baby from a woman infected with COVID‐19.

New blood-borne virus infections among organ transplant recipients: An Australian data-linked cohort study examining donor transmissions and other HIV, hepatitis C and hepatitis B notifications, 2000-2015

BACKGROUND

Blood-borne viral infections can complicate organ transplantation. Systematic monitoring to distinguish donor-transmitted infections from other new infections post transplant is challenging. Administrative health data can be informative. We aimed to quantify post-transplant viral infections, specifically those transmitted by donors and those reactivating or arising new in recipients.

METHODS

We linked transplant registries with administrative health data for all solid organ donor-recipient pairs in New South Wales, Australia, 2000-2015. All new recipient notifications of hepatitis B (HBV), C (HCV), or human immunodeficiency virus (HIV) after transplant were identified. Proven/probable donor transmissions within 12 months of transplant were classified using an international algorithm.

RESULTS

Of 2120 organ donors, there were 72 with a viral infection (9/72 active, 63/72 past). These 72 donors donated to 173 recipients, of whom 24/173 already had the same infection as their donor, and 149/173 did not, so were at risk of donor transmission. Among those at risk, 3/149 recipients had proven/probable viral transmissions (1 HCV, 2 HBV); none were unrecognized by donation services. There were no deaths from transmissions. There were no donor transmissions from donors without known blood-borne viruses. An additional 68 recipients had new virus notifications, of whom 2/68 died, due to HBV infection.

CONCLUSION

This work confirms the safety of organ donation in an Australian cohort, with no unrecognized viral transmissions and most donors with viral infections not transmitting the virus. This may support targeted increases in donation from donors with viral infections. However, other new virus notifications post transplant were substantial and are preventable. Data linkage can enhance current biovigilance systems.

Clinical Outcomes Associated With Escherichia coli Infections in Adults With Cystic Fibrosis: A Cohort Study

Background

Analysis of “emerging” pathogens in cystic fibrosis (CF) lung disease has focused on unique pathogens that are rare in other human diseases or are drug resistant. Escherichia coli is recovered in the sputum of up to 25% of patients with CF, yet little is known about the epidemiology or clinical impact of infection.

Methods

We studied patients attending a Canadian adult CF clinic who had positive sputum cultures for E coli from 1978 to 2016. Infection was categorized as transient or persistent (≥3 positive sputum cultures, spanning >6 months). Those with persistent infection were matched 2:1 with age, sex, and time-period controls without history of E coli infection, and mixed-effects models were used to assess pulmonary exacerbation (PEx) frequency, lung function decline, hospitalization, and intravenous antibiotic days.

Results

Forty-five patients (12.3%) had E coli recovered from sputum samples between 1978 and 2016, and 18 patients (40%) developed persistent infection. Nine patients (24%) had PEx at incident infection, and increased bioburden was predictive of exacerbation (P = .03). Risk factors for persistent infection included lower nutritional status (P < .001) and lower lung function (P = .009), but chronic infection with Pseudomonas aeruginosa was protective. There was no difference in annual lung function decline, need for hospitalization or intravenous antibiotics, or risk of PEx in patients with persistent infection.

Conclusions

Persistent E coli infection was frequent and was more common in CF patients with low nutritional status and lung function. However, this does not predict clinical decline. Multicenter studies would allow better characterization of the epidemiology and clinical impact of E coli infection.

Human Papillomavirus Viral Load and Transmission in Young, Recently Formed Heterosexual Couples

BACKGROUND

We studied the association between human papillomavirus (HPV) viral load (VL) and HPV concordance.

METHODS

The HITCH cohort study included young, heterosexual, recently formed, sexually active couples. Questionnaires and genital samples were collected at 0 and 4 months. Samples were tested for HPV DNA by polymerase chain reaction (PCR; Linear Array). VLs of HPV6/11/16/18/31/42/51 were quantified using type-specific real-time PCR. Correlations between VL and type-specific HPV prevalence and incidence were evaluated using multilevel, mixed-effects linear/logistic regression models.

RESULTS

We included 492 couples. VLs were higher in penile than vaginal samples. VL at subsequent visits correlated significantly within men (r, 0.373), within women (r, 0.193), and within couples (r range: 0.303-0.328). Men with high VL had more type-specific persistent HPV infections (odds ratio [OR], 4.6 [95% confidence interval {CI}, 2.0-10.5]). High VL in men was associated with prevalent (OR, 5.3 [95% CI, 2.5-11.2]) and incident (OR, 6.7 [95% CI, 1.5-30.7]) type-specific HPV infections in their partner. Women's VL was associated with type-specific HPV prevalence in their partner at the same (OR, 5.9) and subsequent (OR, 4.7) visit.

CONCLUSIONS

Persistent HPV infections have limited VL fluctuations. VL between sex partners are correlated and seem predictive of transmission episodes.

Awareness, Attitude and Practice Regarding Disinfection and Handling of Extracted Teeth among the Students in a Dental College in India

Objective:

The main objective of this study is to assess about the awareness, attitude, and practice regarding disinfection and handling of extracted teeth among the students of a dental college in Odisha, India.

Materials and Methods:

The survey was done with a self-designed questionnaire distributed among the students of a dental college in Odisha, India. Data analysis was done using the Statistical Package for the Social Sciences Software (SPSS for Windows, Version 16.0., Released 2007, Chicago, SPSS Inc.) and the results obtained.

Results:

Of the many methods available, the safest and practical methods to sterilize and disinfect the extracted human teeth could be autoclaving, submersion in 10% formalin and 5.25% sodium hypochlorite solutions. In addition, it was found that there is a significant need to educate the potential handlers of such extracted teeth about the latest statuary protocol and guidelines.

Conclusion:

Most of the participants in the study were aware of the established safety protocols regarding how to handle the pathogenic specimens and were putting in practice those standardized guidelines. But still another good number of handlers need to change their casual attitude while following the safety guidelines so as to protect themselves, others and the environment from the pathogenic clinical specimens.

Listeria, Then and Now: A Call to Reevaluate Patient Teaching Based on Analysis of US Federal Databases, 1998-2016

INTRODUCTION

Listeria monocytogenes is a foodborne pathogen capable of crossing the placental-fetal barrier; infection with the bacterium causes listeriosis. An exposed fetus may suffer blindness, neurological damage including meningitis, or even death. The adverse consequences of listeriosis place the infection on the federally reportable disease list. Primary prevention relies on women avoiding 6 categories of foods most likely to be contaminated with L monocytogenes, as indicated in guidelines developed by the Centers for Disease Control and Prevention (CDC), adapted by the American College of Obstetricians and Gynecologists (ACOG) in 2014, and reaffirmed without changes by ACOG in 2016. This report contains a critical evaluation of United States listeriosis prevention guidelines.

METHODS

Between 1998 and 2016, there were 876 identified listeriosis events documented in the illness and recall databases maintained by the CDC, Food and Drug Administration (FDA), and United States Department of Agriculture - Food Safety and Inspection Service (USDA-FSIS). Each contaminated food was manually compared to the existing listeriosis avoidance guidelines, placing each event within or outside the guidelines. Trends were analyzed over time.

RESULTS

Database analysis demonstrates that prior to the year 2000, abiding by the current guidelines would have prevented all reported listeriosis cases. However, in 2015 and 2016, only 5% of confirmed L monocytogenes infections originated from the 6 food groups listed in the CDC and ACOG guidelines. Similar trends emerged for food processing plant recalls (USDA-FSIS database) and grocery store recalls (FDA database). The total number of listeriosis illnesses in the United States doubled from 2007 to 2014.

DISCUSSION

A gradual shift in detection of L monocytogenes contamination in ready-to-eat meals, frozen foods, and ready-to-eat salads has occurred. Another emerging culprit is pasteurized dairy products. Revision of listeriosis avoidance guidelines by a consensus-seeking, multidisciplinary task force, is needed.

Impact of point-of-care management on the transmission of anogenital gonococcal infections among men who have sex with men in Amsterdam: a mathematical modelling and cost-effectiveness study

OBJECTIVE

Point-of-care (POC) management may avert ongoing transmissions occurring between testing and treatment or due to loss to follow-up. We modelled the impact of POC management of anogenital gonorrhoea (with light microscopic evaluation of Gram stained smears) among men who have sex with men (MSM) on gonorrhoea prevalence and testing and treatment costs.

METHODS

Data concerning costs and sexual behaviour were collected from the STI clinic of Amsterdam. With a deterministic model for gonorrhoea transmission, we calculated the prevalence of gonorrhoea in MSM in Amsterdam and the numbers of consultations at our clinic over 5 years, in three testing scenarios: POC for symptomatic MSM only (currently routine), POC for all MSM and no POC for MSM.

RESULTS

Among MSM, 34.7% (109/314) had sexual contacts in the period between testing and treatment, of whom 22.9% (25/109) had unprotected anal intercourse. Expanding POC testing from symptomatic MSM to all MSM could result in an 11% decrease (IQR, 8%-15%) in gonorrhoea prevalence after 5 years and a cost increase of 8.6% (€2.40) per consultation and €86 118 overall (+8.3%). Switching from POC testing of symptomatic MSM to no POC testing could save €1.83 per consultation (6.5%) and €54 044 (-5.2%) after 5 years with a 60% (IQR, 26%-127%) gonorrhoea prevalence increase. Overtreatment was 2.1% (30/1411) with POC for symptomatic MSM only and 4.1% (68/1675) with POC for all MSM.

CONCLUSIONS

In the Amsterdam setting, possible abandonment of POC testing of symptomatic MSM because of budget cuts could result in a considerable increase in gonorrhoea prevalence against a reduction in costs per consultation. Expanding POC testing to all MSM could result in a modest reduction in prevalence and a cost increase. While the costs and outcomes depend on specific local characteristics, the developed framework of this study is useful to evaluate POC management in other settings.

The STRATAA study protocol: a programme to assess the burden of enteric fever in Bangladesh, Malawi and Nepal using prospective population census, passive surveillance, serological studies and healthcare utilisation surveys

INTRODUCTION

Invasive infections caused by Salmonella enterica serovar Typhi and Paratyphi A are estimated to account for 12-27 million febrile illness episodes worldwide annually. Determining the true burden of typhoidal Salmonellae infections is hindered by lack of population-based studies and adequate laboratory diagnostics.The Strategic Typhoid alliance across Africa and Asia study takes a systematic approach to measuring the age-stratified burden of clinical and subclinical disease caused by typhoidal Salmonellae infections at three high-incidence urban sites in Africa and Asia. We aim to explore the natural history of Salmonella transmission in endemic settings, addressing key uncertainties relating to the epidemiology of enteric fever identified through mathematical models, and enabling optimisation of vaccine strategies.

METHODS/DESIGN

Using census-defined denominator populations of ≥100 000 individuals at sites in Malawi, Bangladesh and Nepal, the primary outcome is to characterise the burden of enteric fever in these populations over a 24-month period. During passive surveillance, clinical and household data, and laboratory samples will be collected from febrile individuals. In parallel, healthcare utilisation and water, sanitation and hygiene surveys will be performed to characterise healthcare-seeking behaviour and assess potential routes of transmission. The rates of both undiagnosed and subclinical exposure to typhoidal Salmonellae (seroincidence), identification of chronic carriage and population seroprevalence of typhoid infection will be assessed through age-stratified serosurveys performed at each site. Secondary attack rates will be estimated among household contacts of acute enteric fever cases and possible chronic carriers.

ETHICS AND DISSEMINATION

This protocol has been ethically approved by the Oxford Tropical Research Ethics Committee, the icddr,b Institutional Review Board, the Malawian National Health Sciences Research Committee and College of Medicine Research Ethics Committee and Nepal Health Research Council. The study is being conducted in accordance with the principles of the Declaration of Helsinki and Good Clinical Practice. Informed consent was obtained before study enrolment. Results will be submitted to international peer-reviewed journals and presented at international conferences.

TRIAL REGISTRATION NUMBER

ISRCTN 12131979.

ETHICS REFERENCES

Oxford (Oxford Tropical Research Ethics Committee 39-15).Bangladesh (icddr,b Institutional Review Board PR-15119).Malawi (National Health Sciences Research Committee 15/5/1599).Nepal (Nepal Health Research Council 306/2015).

Prevalence and Outcomes of Achromobacter Species Infections in Adults with Cystic Fibrosis: a North American Cohort Study

Achromobacter species are increasingly being detected in cystic fibrosis (CF) patients, with an unclear epidemiology and impact. We studied a cohort of patients attending a Canadian adult CF clinic who had positive sputum cultures for Achromobacter species in the period from 1984 to 2013. Infection was categorized as transient or persistent (≥50% positive cultures for 1 year). Those with persistent infection were matched 2:1 with age-, sex-, and time-matched controls without a history of Achromobacter infection, and mixed-effects models were used to assess pulmonary exacerbation (PEx) frequency and lung function decline. Isolates from a biobank were retrospectively assessed, identified to the species level by nrdA sequencing, and genotyped using pulsed-field gel electrophoresis (PFGE). Thirty-four patients (11% of those in our clinic), with a median age of 24 years (interquartile range [IQR], 20.3 to 29.8 years), developed Achromobacter infection. Ten patients (29%) developed persistent infection. Persistence did not denote permanence, as most patients ultimately cleared infection, often after years. Patients were more likely to experience PEx at incident isolation than at prior or subsequent visits (odds ratio [OR], 2.7 [95% confidence interval {CI}, 1.2 to 6.7]; P = 0.03). Following persistent infection, there was no difference in annual lung function decline (-1.08% [95% CI, -2.73 to 0.57%] versus -2.74% [95% CI, -4.02 to 1.46%]; P = 0.12) or the odds of PEx (OR, 1.21 [95% CI, 0.45 to 3.28]; P = 0.70). Differential virulence among Achromobacter species was not observed, and no cases of transmission occurred. We demonstrated that incident Achromobacter infection was associated with a greater risk of PEx; however, neither transient nor chronic infection was associated with a worsened long-term prognosis. Large, multicenter studies are needed to clarify the clinical impact, natural history, and transmissibility of Achromobacter.

Influence of observable and unobservable exposure on the patient's risk of acquiring influenza-like illness at hospital

During outbreaks of hospital-acquired influenza-like illness (HA-ILI) healthcare workers (HCWs), patients, and visitors are each a source of infection for the other. Quantifying the effects of these various exposures will help improve prevention and control of HA-ILI outbreaks. We estimated the attributability of HA-ILI to: (1) exposure to recorded or unrecorded sources; (2) exposure to contagious patient or contagious HCW; (3) exposure during observable or unobservable contagious period of the recorded sources; and, (4) the moment of exposure. Among recorded sources, 59% [95% credible interval (CrI) 34-83] of HA-ILI of patients was associated with exposure to contagious patients and 41% (95% CrI 17-66) with exposure to contagious HCWs. Exposure during the unobservable contagiousness period of source patients accounted for 49% (95% CrI 19-75) of HA-ILI, while exposure during the unobservable contagiousness period of source HCWs accounted for 82% (95% CrI 51-99) of HA-ILI. About 80% of HA-ILIs were associated with exposure 1 day earlier. Secondary cases of HA-ILI might appear as soon as the day after the detection of a primary case highlighting the explosive nature of HA-ILI spread. Unobservable transmission was the main cause of HA-ILI transmission suggesting that symptom-based control measures alone might not prevent hospital outbreaks. The results support the rapid implementation of interventions to control influenza transmission.

A Risk Assessment Scheme of Infection Transmission Indoors Incorporating the Impact of Resuspension

A new risk assessment scheme was developed to quantify the impact of resuspension to infection transmission indoors. Airborne and surface pathogenic particle concentration models including the effect of two major resuspension scenarios (airflow-induced particle resuspension [AIPR] and walking-induced particle resuspension [WIPR]) were derived based on two-compartment mass balance models and validated against experimental data found in the literature. The inhalation exposure to pathogenic particles was estimated using the derived airborne concentration model, and subsequently incorporated into a dose-response model to assess the infection risk. Using the proposed risk assessment scheme, the influences of resuspension towards indoor infection transmission were examined by two hypothetical case studies. In the case of AIPR, the infection risk increased from 0 to 0.54 during 0-0.5 hours and from 0.54 to 0.57 during 0.5-4 hours. In the case of WIPR, the infection risk increased from 0 to 0.87 during 0-0.5 hours and from 0.87 to 1 during 0.5-4 hours. Sensitivity analysis was conducted based on the design-of-experiments method and showed that the factors that are related to the inspiratory rate of viable pathogens and pathogen virulence have the most significant effect on the infection probability under the occurrence of AIPR and WIPR. The risk assessment scheme could serve as an effective tool for the risk assessment of infection transmission indoors.

Preventing HIV Transmission in Nigeria: Role of the Dentists

BACKGROUND

As healthcare providers, dentists are in a unique position to foster behavioural changes that are needed to stem the spread of HIV infection. This study was conducted to assess the role of dentists in the prevention of HIV transmission in Nigeria.

METHODS

This descriptive cross-sectional survey was conducted from June 2006 to January 2007. A multi-stage sampling technique was used to select 300 practising dentists from all parts of Nigeria. Data were collected through a self-administered questionnaire that focused on dentist demographic details, attitudes towards treating HIV-infected persons, involvement in public or clinic-based patient education on HIV and infection control.

RESULTS

Two hundred and fifty-seven questionnaires were returned completed, constituting an 86% response rate. The majority of respondents (77.8%) had their dental practice in the southern part of Nigeria, and 89% were in the age bracket of 21-40 years. HIV education by dentists was ranked as poor, as less than a quarter of respondents routinely educated patients on HIV in the clinic. Only a few dentists (33.3%) were involved in public enlightenment programme on HIV in the previous 12 months. Most of the respondents (93%) reported a willingness to treat HIV-infected patients while observing universal precautions. Good infection barrier practices were adopted by 89.9% of dentists, and disposable cartridges for local anaesthetic agents and dental needles were not reused by 93.4% of the respondents. Autoclaving was the most widely used sterilization method (73.2%), but less than half of the respondents knew how to ascertain whether sterilization was effective.

CONCLUSION

This study revealed that efforts by Nigerian dentists to prevent HIV transmission are presently less than optimal. Therefore, there is a need for sensitisation and motivation through seminars, workshops and lectures.

A study quantifying the hand-to-face contact rate and its potential application to predicting respiratory tract infection

A substantial portion of human respiratory tract infection is thought to be transmitted via contaminated hand contact with the mouth, eyes, and/or nostrils. Thus, a key risk factor for infection transmission should be the rate of hand contact with these areas termed target facial membranes. A study was conducted in which 10 subjects were each videotaped for 3 hr while performing office-type work in isolation from other persons. The number of contacts to the eyes, nostrils, and lips was scored during subsequent viewing of the tapes. The total contacts per subject had sample mean x = 47 and sample standard deviation s = 34. The average total contact rate per hour was 15.7. The authors developed a relatively simple algebraic model for estimating the dose of pathogens transferred to target facial membranes during a defined exposure period. The model considers the rate of pathogen transfer to the hands via contact with contaminated environmental surfaces, and the rate of pathogen loss from the hands due to pathogen die-off and transfer from the hands to environmental surfaces and to target facial membranes during touching. The estimation of infection risk due to this dose also is discussed. A hypothetical but plausible example involving influenza A virus transmission is presented to illustrate the model.