West Nile virus: review of the literature Petersen, Lyle R; Brault, Aaron C; Nasci, Roger S
JAMA : the journal of the American Medical Association,
07/2013, Volume:
310, Issue:
3
Journal Article
Peer reviewed
Open access
Since its introduction in North America in 1999, West Nile virus has produced the 3 largest arboviral neuroinvasive disease outbreaks ever recorded in the United States.
To review the ecology, ...virology, epidemiology, clinical characteristics, diagnosis, prevention, and control of West Nile virus, with an emphasis on North America.
PubMed electronic database was searched through February 5, 2013. United States national surveillance data were gathered from the Centers for Disease Control and Prevention.
West Nile virus is now endemic throughout the contiguous United States, with 16,196 human neuroinvasive disease cases and 1549 deaths reported since 1999. More than 780,000 illnesses have likely occurred. To date, incidence is highest in the Midwest from mid-July to early September. West Nile fever develops in approximately 25% of those infected, varies greatly in clinical severity, and symptoms may be prolonged. Neuroinvasive disease (meningitis, encephalitis, acute flaccid paralysis) develops in less than 1% but carries a fatality rate of approximately 10%. Encephalitis has a highly variable clinical course but often is associated with considerable long-term morbidity. Approximately two-thirds of those with paralysis remain with significant weakness in affected limbs. Diagnosis usually rests on detection of IgM antibody in serum or cerebrospinal fluid. Treatment is supportive; no licensed human vaccine exists. Prevention uses an integrated pest management approach, which focuses on surveillance, elimination of mosquito breeding sites, and larval and adult mosquito management using pesticides to keep mosquito populations low. During outbreaks or impending outbreaks, emphasis shifts to aggressive adult mosquito control to reduce the abundance of infected, biting mosquitoes. Pesticide exposure and adverse human health events following adult mosquito control operations for West Nile virus appear negligible.
In North America, West Nile virus has and will remain a formidable clinical and public health problem for years to come.
Since West Nile virus (WNV) emerged in the United States in 1999, 22,999 neuroinvasive disease cases in humans were reported through 2017. These cases have arisen from an estimated seven million ...human infections. Population incidence is geographically heterogeneous and is highest in the West and Midwest. Upwards of 2% of the population in some jurisdictions may become infected during outbreaks. Before universal screening of the United States blood supply, this high infection incidence and that approximately 75% of those infected remain asymptomatic translated into a considerable risk of WNV transfusion transmission despite the short duration of viremia following infection. Universal blood donor screening has nearly eliminated the risk of WNV transfusion transmission, but at enormous cost. WNV transmission via transplanted organs carries extremely high morbidity and mortality. Improved vector surveillance and timely and effective response to surveillance data can reduce the impact of WNV and should remain public health priorities.
Epidemiology of Zika Virus Infection Hills, Susan L.; Fischer, Marc; Petersen, Lyle R.
The Journal of infectious diseases,
12/2017, Volume:
216, Issue:
suppl_10
Journal Article
Peer reviewed
Open access
Long known to be endemic in Africa and Southeast Asia and a rare cause of acute febrile illness, Zika virus (ZIKAV) arose from obscurity when an Asian genotype ZIKAV caused an outbreak of mild ...febrile illness in 2007 in Yap State, Federated States of Micronesia. Subsequent viral spread in the Pacific led to a large outbreak in French Polynesia commencing in 2013. After its recognition in the Americas through March 2017, the Pan American Health Organization has received reports of >750 000 suspected and laboratory-confirmed cases of autochthonous ZIKAV transmission. Outbreaks in most countries in the Americas peaked in early to mid-2016. Increased surveillance in several Southeast Asian counties has led to increased case recognition, including an outbreak in Singapore, and the first reports of birth defects linked to ZIKAV in the region. As of April 2017, the World Health Organization reported 84 countries or territories with current or previous ZIKAV transmission.
Abstract
Background
Reports suggest that some persons previously infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lack detectable immunoglobulin G (IgG) antibodies. We aimed ...to determine the proportion IgG seronegative and predictors for seronegativity among persons previously infected with SARS-CoV-2.
Methods
We analyzed serologic data collected from healthcare workers and first responders in New York City and the Detroit metropolitan area with a history of a positive SARS-CoV-2 reverse-transcription polymerase chain reaction (RT-PCR) test result and who were tested for IgG antibodies to SARS-CoV-2 spike protein at least 2 weeks after symptom onset.
Results
Of 2547 persons with previously confirmed SARS-CoV-2 infection, 160 (6.3%) were seronegative. Of 2112 previously symptomatic persons, the proportion seronegative slightly increased from 14 to 90 days post symptom onset (P = .06). The proportion seronegative ranged from 0% among 79 persons previously hospitalized to 11.0% among 308 persons with asymptomatic infections. In a multivariable model, persons who took immunosuppressive medications were more likely to be seronegative (31.9%; 95% confidence interval CI, 10.7%–64.7%), while participants of non-Hispanic Black race/ethnicity (vs non-Hispanic White; 2.7%; 95% CI, 1.5%–4.8%), with severe obesity (vs under/normal weight; 3.9%; 95% CI, 1.7%–8.6%), or with more symptoms were less likely to be seronegative.
Conclusions
In our population with previous RT-PCR–confirmed infection, approximately 1 in 16 persons lacked IgG antibodies. Absence of antibodies varied independently by illness severity, race/ethnicity, obesity, and immunosuppressive drug therapy. The proportion seronegative remained relatively stable among persons tested up to 90 days post symptom onset.
Our data suggest that a sizable proportion of persons do not have immunoglobulin G antibodies following severe acute respiratory syndrome coronavirus 2 infection, which independently relates to illness severity, race/ethnicity, obesity, and immunosuppressive medication. These factors should be considered when interpreting results of serologic testing.
To estimate seroprevalence of severe acute respiratory syndrome 2 (SARS-CoV-2) among healthcare, first response, and public safety personnel, antibody testing was conducted in emergency medical ...service agencies and 27 hospitals in the Detroit, Michigan, USA, metropolitan area during May-June 2020. Of 16,403 participants, 6.9% had SARS-CoV-2 antibodies. In adjusted analyses, seropositivity was associated with exposure to SARS-CoV-2-positive household members (adjusted odds ratio aOR 6.18, 95% CI 4.81-7.93) and working within 15 km of Detroit (aOR 5.60, 95% CI 3.98-7.89). Nurse assistants (aOR 1.88, 95% CI 1.24-2.83) and nurses (aOR 1.52, 95% CI 1.18-1.95) had higher likelihood of seropositivity than physicians. Working in a hospital emergency department increased the likelihood of seropositivity (aOR 1.16, 95% CI 1.002-1.35). Consistently using N95 respirators (aOR 0.83, 95% CI 0.72-0.95) and surgical facemasks (aOR 0.86, 95% CI 0.75-0.98) decreased the likelihood of seropositivity.
Understanding the risk of birth defects associated with Zika virus infection during pregnancy may help guide communication, prevention, and planning efforts. In the absence of Zika virus, ...microcephaly occurs in approximately 7 per 10 000 live births.
To estimate the preliminary proportion of fetuses or infants with birth defects after maternal Zika virus infection by trimester of infection and maternal symptoms.
Completed pregnancies with maternal, fetal, or infant laboratory evidence of possible recent Zika virus infection and outcomes reported in the continental United States and Hawaii from January 15 to September 22, 2016, in the US Zika Pregnancy Registry, a collaboration between the CDC and state and local health departments.
Laboratory evidence of possible recent Zika virus infection in a maternal, placental, fetal, or infant sample.
Birth defects potentially Zika associated: brain abnormalities with or without microcephaly, neural tube defects and other early brain malformations, eye abnormalities, and other central nervous system consequences.
Among 442 completed pregnancies in women (median age, 28 years; range, 15-50 years) with laboratory evidence of possible recent Zika virus infection, birth defects potentially related to Zika virus were identified in 26 (6%; 95% CI, 4%-8%) fetuses or infants. There were 21 infants with birth defects among 395 live births and 5 fetuses with birth defects among 47 pregnancy losses. Birth defects were reported for 16 of 271 (6%; 95% CI, 4%-9%) pregnant asymptomatic women and 10 of 167 (6%; 95% CI, 3%-11%) symptomatic pregnant women. Of the 26 affected fetuses or infants, 4 had microcephaly and no reported neuroimaging, 14 had microcephaly and brain abnormalities, and 4 had brain abnormalities without microcephaly; reported brain abnormalities included intracranial calcifications, corpus callosum abnormalities, abnormal cortical formation, cerebral atrophy, ventriculomegaly, hydrocephaly, and cerebellar abnormalities. Infants with microcephaly (18/442) represent 4% of completed pregnancies. Birth defects were reported in 9 of 85 (11%; 95% CI, 6%-19%) completed pregnancies with maternal symptoms or exposure exclusively in the first trimester (or first trimester and periconceptional period), with no reports of birth defects among fetuses or infants with prenatal exposure to Zika virus infection only in the second or third trimesters.
Among pregnant women in the United States with completed pregnancies and laboratory evidence of possible recent Zika infection, 6% of fetuses or infants had evidence of Zika-associated birth defects, primarily brain abnormalities and microcephaly, whereas among women with first-trimester Zika infection, 11% of fetuses or infants had evidence of Zika-associated birth defects. These findings support the importance of screening pregnant women for Zika virus exposure.
Case-based surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection likely underestimates the true prevalence of infections. Large-scale seroprevalence surveys can ...better estimate infection across many geographic regions.
To estimate the prevalence of persons with SARS-CoV-2 antibodies using residual sera from commercial laboratories across the US and assess changes over time.
This repeated, cross-sectional study conducted across all 50 states, the District of Columbia, and Puerto Rico used a convenience sample of residual serum specimens provided by persons of all ages that were originally submitted for routine screening or clinical management from 2 private clinical commercial laboratories. Samples were obtained during 4 collection periods: July 27 to August 13, August 10 to August 27, August 24 to September 10, and September 7 to September 24, 2020.
Infection with SARS-CoV-2.
The proportion of persons previously infected with SARS-CoV-2 as measured by the presence of antibodies to SARS-CoV-2 by 1 of 3 chemiluminescent immunoassays. Iterative poststratification was used to adjust seroprevalence estimates to the demographic profile and urbanicity of each jurisdiction. Seroprevalence was estimated by jurisdiction, sex, age group (0-17, 18-49, 50-64, and ≥65 years), and metropolitan/nonmetropolitan status.
Of 177 919 serum samples tested, 103 771 (58.3%) were from women, 26 716 (15.0%) from persons 17 years or younger, 47 513 (26.7%) from persons 65 years or older, and 26 290 (14.8%) from individuals living in nonmetropolitan areas. Jurisdiction-level seroprevalence over 4 collection periods ranged from less than 1% to 23%. In 42 of 49 jurisdictions with sufficient samples to estimate seroprevalence across all periods, fewer than 10% of people had detectable SARS-CoV-2 antibodies. Seroprevalence estimates varied between sexes, across age groups, and between metropolitan/nonmetropolitan areas. Changes from period 1 to 4 were less than 7 percentage points in all jurisdictions and varied across sites.
This cross-sectional study found that as of September 2020, most persons in the US did not have serologic evidence of previous SARS-CoV-2 infection, although prevalence varied widely by jurisdiction. Biweekly nationwide testing of commercial clinical laboratory sera can play an important role in helping track the spread of SARS-CoV-2 in the US.
Chikungunya: epidemiology Petersen, Lyle R; Powers, Ann M
F1000 research,
2016, Volume:
5
Journal Article
Peer reviewed
Open access
Chikungunya virus is a mosquito-borne alphavirus that causes fever and debilitating joint pains in humans. Joint pains may last months or years. It is vectored primarily by the tropical and ...sub-tropical mosquito, Aedes aegypti, but is also found to be transmitted by Aedes albopictus, a mosquito species that can also be found in more temperate climates. In recent years, the virus has risen from relative obscurity to become a global public health menace affecting millions of persons throughout the tropical and sub-tropical world and, as such, has also become a frequent cause of travel-associated febrile illness. In this review, we discuss our current understanding of the biological and sociological underpinnings of its emergence and its future global outlook.
We conducted a serologic survey in public service agencies in New York City, New York, USA, during May-July 2020 to determine prevalence of severe acute respiratory syndrome coronavirus 2 ...(SARS-CoV-2) infection among first responders. Of 22,647 participants, 22.5% tested positive for SARS-CoV-2-specific antibodies. Seroprevalence for police and firefighters was similar to overall seroprevalence; seroprevalence was highest in correctional staff (39.2%) and emergency medical technicians (38.3%) and lowest in laboratory technicians (10.1%) and medicolegal death investigators (10.8%). Adjusted analyses demonstrated association between seropositivity and exposure to SARS-CoV-2-positive household members (adjusted odds ratio aOR 3.52 95% CI 3.19-3.87), non-Hispanic Black race or ethnicity (aOR 1.50 95% CI 1.33-1.68), and severe obesity (aOR 1.31 95% CI 1.05-1.65). Consistent glove use (aOR 1.19 95% CI 1.06-1.33) increased likelihood of seropositivity; use of other personal protective equipment had no association. Infection control measures, including vaccination, should be prioritized for frontline workers.
PDF
