Measles, mumps, rubella, and human parvovirus B19 infections and neurologic disease

Isolation, genome analysis and comparison of a novel parainfluenza virus 5 from a Siberian tiger (Panthera tigris)

Paramyxoviruses are important pathogens affecting various animals, including mammals and humans. Parainfluenza virus 5 (PIV5)-a member of the family Paramyxoviridae-is a major threat to the health of mammals and humans. However, studies on terrestrial wild animals infected with PIV5 are scanty. In this study, we utilized reverse transcription PCR to detect PIV5 infection in the visceral organ tissues of a Siberian tiger (Panthera tigris ssp. altaica) with vomiting, diarrhea, and dyspnea before its death. A novel PIV5 (named SR strain) with a slowly progressive cytopathic effect was isolated in Vero cells and validated using a transmission electron microscope. Full-length sequencing and analysis revealed that the whole genome of the PIV5 SR strain contained 15,246 nucleotides (nt) and seven non-overlapping genes (3'-N-V/P-M-F-SH-HN-L-5') encoding eight proteins. Phylogenetic analysis of three PIV5 strains identified in the same zoo confirmed that PIV5 strains SR and ZJQ-221 shared the closest genetic relationship as they were clustered in the same branch, while the recently found Siberian tiger strain SZ2 kept a certain distance and formed a relatively unique branch. Furthermore, mutations of nt and amino acids (aa) between strains ZJQ-221, SR, and SZ2 were identified. In summary, we report the identification and genomic characterization of a novel PIV5 strain SR isolated in a Siberian tiger, which may help future research on interspecific transmission mechanisms.

Metabolomics Approaches for the Diagnosis, Treatment, and Better Disease Management of Viral Infections

Metabolomics is an analytical approach that involves profiling and comparing the metabolites present in biological samples. This scoping review article offers an overview of current metabolomics approaches and their utilization in evaluating metabolic changes in biological fluids that occur in response to viral infections. Here, we provide an overview of metabolomics methods including high-throughput analytical chemistry and multivariate data analysis to identify the specific metabolites associated with viral infections. This review also focuses on data interpretation and applications designed to improve our understanding of the pathogenesis of these viral diseases.

Rubella seroprevalence among pregnant women in the region of Rabat, Morocco: a cross-sectional study

OBJECTIVES

The aim of the present research is to update data on the seroprevalence of rubella and to identify the associated risk factors among pregnant women in the Rabat region of Morocco in order to take immediate action to monitor the virus.

DESIGN

A cross-sectional study.

SETTING

The study was conducted at Ibn Sina University Hospital and at referral healthcare centres in the region of Rabat.

PARTICIPANTS

A total of 502 pregnant women (mean age 29.7±6.3 years, range 17-44 years) attending the maternity department during 8 months were selected for serological testing.

OUTCOME MEASURES

A structured questionnaire was used to obtain sociodemographic, reproductive and clinical characteristics after obtaining written informed consent. Venous blood samples were collected to determine rubella-specific IgG antibodies using an automated chemiluminescent microparticle immunoassay (ARCHITECT i1000SR and i2000SR, Abbott Diagnostics).

RESULTS

Antirubella IgG antibodies (≥10 IU/mL) were found in 408 (85.9%) pregnant women examined. The rate of susceptibility to rubella virus infection among pregnant women was found to be 14.1%. These protective rates were found to differ significantly between uneducated pregnant women (80.9%) and those with university-level education (95.5%) (p=0.02). Pregnant women in the 17-24, 25-34 and 35-44 years age groups accounted for 92.5%, 85.2% and 82.8%, respectively (p=0.015). Also, IgG seropositivity status was found to differ significantly between multiparous (83.3%) and primiparous (92.5%) pregnant women (p=0.01). None of the other characteristics was significantly associated with rubella infections.

CONCLUSION

Vaccination programmes need to be updated to ensure that campaigns reach their specified goals. Thus, implementing an effective, large-scale screening programme for congenital rubella infection in different regions of Morocco is highly recommended. On the other hand, seronegative pregnant women should be given special preventive care and health education about rubella transmission and congenital rubella syndrome sequelae.

Trends and Treatment of Sub-Acute Sclerosing Panencephalitis: An Updated Review

Measles infection, caused by the “Rubeola” virus is a highly contagious disease with outrageously fatal consequences. Initiating with a variety of symptoms including fever, cough, conjunctivitis, and runny nose, it can lead to more severe sequelae including sub-acute sclerosing pan-encephalitis which is a potentially fatal and serious complication of measles. The lackluster vaccination processes in underdeveloped areas of the world due to suboptimal immunization programs, scarce resources, and insufficient political constancy still leads to increased cases of measles and its complications. A variety of management programs including the use of several medications have been introduced according to the literature in order to counter this dreadful disease. In this review article, we focus on assessment of the previous literature and discussing the possible treatment modalities of this currently irremediable disease.

Burden of Rubella virus infection among females attending tertiary care hospitals of Odisha, India: a need for adult women vaccination

Rubella is a contagious disease caused by rubella virus leading to adverse outcomes among pregnant women including abortions, low birth weight, stillbirths and congenital rubella syndrome (CRS) in the baby. If not pregnant, the clinical manifestations are mild and self-limiting. In this hospital based cross-sectional study, 1985 blood samples were collected from females attending outpatient services of various hospitals to serologically detect Rubella infection. Rubella antibodies namely Immunoglobulin M (IgM)/Immunoglobulin G (IgG) were detected through enzyme linked immunosorbent assay (ELISA) or by identifying virus through polymerase chain reaction (PCR). From the total enrolled participants, 1951 samples were tested with age ranging from 16 to 38 years. Among the positive samples, about 60% patients had IgG antibodies as compared to less than 1% IgM and 0.40% by PCR. Out of 1951 samples, 7/849 (0.82%) and 651/1070 (60.8%) had IgM & IgG rubella antibodies respectively. The odds of having abortion was [OR-13.14 (4.94-34.97)] among anti-rubella positive and primi-gravida [OR-43.6 (5.9-322)] women. Therefore, vaccination of women against rubella before planning of pregnancy or at adolescence seems to be the need of hour to avoid the ill consequences during pregnancy as well as for the new born baby.

The neurological sequelae of pandemics and epidemics

Neurological manifestations in pandemics frequently cause short and long-term consequences which are frequently overlooked. Despite advances in the treatment of infectious diseases, nervous system involvement remains a challenge, with limited treatments often available. The under-recognition of neurological manifestations may lead to an increase in the burden of acute disease as well as secondary complications with long-term consequences. Nervous system infection or dysfunction during pandemics is common and its enduring consequences, especially among vulnerable populations, are frequently forgotten. An improved understanding the possible mechanisms of neurological damage during epidemics, and increased recognition of the possible manifestations is fundamental to bring insights when dealing with future outbreaks. To reverse this gap in knowledge, we reviewed all the pandemics, large and important epidemics of human history in which neurological manifestations are evident, and described the possible physiological processes that leads to the adverse sequelae caused or triggered by those pathogens.

First complete genome sequence of parainfluenza virus 5 isolated from lesser panda

Parainfluenza virus 5 (PIV5) is widespread in mammals and humans. Up to now, there is little information about PIV5 infection in lesser pandas. In this study, a PIV5 variant (named ZJQ-221) was isolated from a lesser panda with respiratory disease in Guangzhou zoo in Guangdong province, southern China. The full-length genome of ZJQ-221 was found to be 15,246 nucleotides and consisted of seven non-overlapping genes encoding eight proteins (i.e., NP, V, P, M, F, SH, HN and L). Sequence alignment and genetic analysis revealed that ZJQ-221 shared a close relationship with a PIV5 strain of canine-origin (1168-1) from South Korea. The findings of this study confirm the presence of PIV5 in lesser panda and indicate this mammal as a possible natural reservoir. Furthermore they highlight the urgent need to strengthen viral surveillance and control of PIV5 in zoo animals.

Rubella Immune Status in Pregnant Women in a Northern Mexican City

BACKGROUND

The seroepidemiology of rubella virus infection in pregnant women in northern Mexico is largely unknown. We sought to determine the seroprevalence of rubella virus infection in pregnant women in the northern Mexican city of Durango, Mexico. Seroprevalence association with the socio-demographic, clinical and behavioral characteristics of the pregnant women was also investigated.

METHODS

Through a cross-sectional study, we determined the seroprevalence of IgG and IgM anti-rubella virus in 279 pregnant women (mean age 29.17 ± 5.96 years; range 15 - 43 years) attending in a clinic of family medicine using enzyme-linked fluorescent assays. A questionnaire was used to obtain the socio-demographic, clinical and behavioral characteristics of the pregnant women. The association of rubella seropositivity and characteristics of the women was assessed by bivariate and multivariate analyses.

RESULTS

Anti-rubella IgG antibodies (≥ 15 IU/mL) were found in 271 (97.1%) of the 279 pregnant women examined. None of the 279 pregnant women were positive for anti-rubella IgM antibodies. Multivariate analysis of socio-demographic, clinical and behavioral variables showed that seroreactivity to rubella virus was positively associated with national trips (OR = 7.39; 95% CI: 1.41 - 38.78; P = 0.01), and negatively associated with age (OR = 0.26; 95% CI: 0.06 - 0.99; P = 0.04).

CONCLUSIONS

Rate of rubella immunity in pregnant women in the northern Mexican city of Durango is high. However, nearly 3% of pregnant women are susceptible to rubella in our setting. Risk factors associated with rubella seropositivity found in this study may be useful for optimal design of preventive measures against rubella and its sequelae.

Seroepidemiology of Rubella in Women Under 25 Years Old Attending Medical Centers in Ahvaz, Iran in 2013

Background:

Rubella is a mild viral infection affecting women of reproductive age, and the fetus in early pregnancy, leading to miscarriage, stillbirth and Congenital Rubella Syndrome.

Objectives:

The present study aimed to assess serum level of anti-rubella antibodies in women younger than 25 years attending medical centers in Ahvaz city.

Patients and Methods:

This descriptive cross-sectional study was conducted on 760 women younger than 25 years attending medical centers in Ahvaz. A sample of 3 mL of venous blood was taken from each woman and ELISA method was used to assess anti-rubella IgG levels. Antibody level more than 11 IU/mL was considered safe. Data was analyzed by SPSS software using Chi-square, ANOVA and Pearson Correlation tests.

Results:

Of total samples, 683 women (88.9%) had immunity against rubella, 80 (10.4%) no immunity and 5 (0.7%) intermediate levels of antibody. Immunity to rubella increased significantly with aging (P = 0.001) and a significant association was found between age and antibody titer (P = 0.001, r = 0.261).

Conclusions:

More than 95% of 15 to 25 year-old women (main reproductive age in Iran) are within acceptable immunity range. Level of immunity to rubella in women of reproductive age in this region appears satisfactory.

Measles fusion machinery is dysregulated in neuropathogenic variants

Paramyxoviruses, including the human pathogen measles virus (MV), enter host cells by fusing their viral envelope with the target cell membrane. This fusion process is driven by the concerted actions of the two viral envelope glycoproteins, the receptor binding protein (hemagglutinin [H]) and the fusion (F) protein. H attaches to specific proteinaceous receptors on host cells; once the receptor engages, H activates F to directly mediate lipid bilayer fusion during entry. In a recent MV outbreak in South Africa, several HIV-positive people died of MV central nervous system (CNS) infection. We analyzed the virus sequences from these patients and found that specific intrahost evolution of the F protein had occurred and resulted in viruses that are "CNS adapted." A mutation in F of the CNS-adapted virus (a leucine-to-tryptophan change present at position 454) allows it to promote fusion with less dependence on engagement of H by the two known wild-type (wt) MV cellular receptors. This F protein is activated independently of H or the receptor and has reduced thermal stability and increased fusion activity compared to those of the corresponding wt F. These functional effects are the result of the single L454W mutation in F. We hypothesize that in the absence of effective cellular immunity, such as HIV infection, MV variants bearing altered fusion machinery that enabled efficient spread in the CNS underwent positive selection.

IMPORTANCE

Measles virus has become a concern in the United States and Europe due to recent outbreaks and continues to be a significant global problem. While live immunization is available, there are no effective therapies or prophylactics to combat measles infection in unprotected people. Additionally, vaccination does not adequately protect immunocompromised people, who are vulnerable to the more severe CNS manifestations of disease. We found that strains isolated from patients with measles virus infection of the CNS have fusion properties different from those of strains previously isolated from patients without CNS involvement. Specifically, the viral entry machinery is more active and the virus can spread, even in the absence of H. Our findings are consistent with an intrahost evolution of the fusion machinery that leads to neuropathogenic MV variants.