Low prevalence of anti-Orthopoxvirus neutralizing antibodies in an urban population of Brazil.

Since 1999, Vaccinia virus (VACV) has been described as a causative agent of bovine vaccinia (BV), a zoonotic disease that occurs mainly in rural areas of Brazil. However, the circulation of VACV in urban environments and its associated burden has been poorly explored. Moreover, the current monkeypox (mpox) outbreak has raised questions regarding the immune status of the worldwide population previous vaccinated against smallpox. Hence, we conducted a cross-sectional study to better understand the prevalence of anti-OPV neutralizing antibodies (NA) and related exposure factors in a susceptible urban population of Brazil. A total of 372 individuals were sampled, yielding an overall seroprevalence of 16.9% (CI95% = 13.4-21.1), and antibodies titers ranging from 100 to 800 neutralizing units/mL. The prevalence of NA among individuals potentially vaccinated against smallpox (≥36 years old [yo]) was 24.9% (IC 95% = 19.5-31.2), and among those unvaccinated (<36yo) was 6.7% (IC 95% = 3.7-11.8). Interestingly, contact with horses was pointed out as an exposure factor for the presence of NA, however, the multivariate logistic regression analysis indicated that age ≥36yo and the presence of vaccine take were independently associated with the presence of anti-OPV NA. Our findings suggest that vulnerable populations could be subclinically exposed to VACV in urban areas, drawing attention to alternative routes of zoonotic VACV exposure. Our data is also important for better strategies to mitigate zoonotic OPV infections mainly among vulnerable populations.

Characteristics and Factors Associated with SARS-CoV-2 Infections in Individuals That Attended Referral Hospitals from Southern Region of Bahia State, Brazil: A Surveillance Network Retrospective Study.

In December 2019, a novel coronavirus was detected in Wuhan, China, and rapidly spread worldwide. In Brazil, to date, there have been more than 20,000,000 confirmed cases of COVID-19 and more than 550,000 deaths. The purpose of the current study was to determine the clinical and epidemiological profile of the population affected by COVID-19 that have attended referral hospitals in Southern region of Bahia State, to better understand the disease and its risk factors in order to enable more appropriate conduct for patients. An observational, descriptive, cross-sectional, exploratory study was conducted using secondary data collected from the Laboratório de Farmacogenômica e Epidemiologia Molecular, Universidade Estadual de Santa Cruz (LAFEM/UESC). Chi-squared and Fisher's exact tests were applied to determine the association between clinical symptoms and laboratory results, and to identify risk factors associated with SARS-CoV-2 infection. A total of 3135 individuals with suspected severe respiratory illness were analyzed and 41.4% of them tested positive for SARS-CoV-2 infection. Male individuals and having comorbidities were risk factors significantly associated with SARS-CoV-2 infection (OR = 1.17 and OR = 1.37, respectively). Interestingly, being a healthcare professional was a significantly protective factor (OR = 0.81, p < 0.001). Our findings highlight the importance of routinely testing the population for early identification of infected individuals, and also provide important information to health authorities and police makers to improve control measures, management, and screening protocols.

High Incidence of Congenital Syphilis after Implementation of the Brazilian Ministry of Health Ordinances Related to Maternal Diagnostics.

The increasing rates of maternal and congenital syphilis (CS) infections are public health concerns and need further investigation in order to provide better assistance in epidemiological surveillance and new strategies for the assistance and prevention of CS. In December 2011, the Brazilian Ministry of Health (BMH) implemented ordinance number 3.242, reinforced in 2012 by ordinance number 77, aiming to improve the quality of the syphilis diagnosis system using rapid tests. Here, we evaluate the incidence, lethality, and possible factors associated with CS in Salvador, Bahia, in the pre-resolution period (2007 to 2011) and post-resolution (2012 to 2016). An observational, ecological time-series study is conducted using secondary data collected from the National Notifiable Diseases Information System (SINAN). Linear regression analysis to estimate increases or reductions in the mean incidence over time is also performed. A total of 5470 CS cases are analyzed. The incidence ranges from 2.1 cases per 1000 live births in 2007 to 17.1 cases per 1000 live births in 2019, showing a progressive increase in incidence over the years and reduction of lethality in the post-resolution period. The number of CS cases reported prior to the implementation of the ordinances (2007-2011) does not reveal a significant increase in the incidence. However, in the post-ordinances period (2012-2019), there is an average increase of the number of CS cases by three times over the years, with an average increase of 1.8 new cases annually. Our findings highlight the importance of diagnosis and support information in strategies for CS prevention. Furthermore, these data show a positive impact of resolutions on the diagnosis and evolution of the disease.

Rabies post-exposure healthcare-seeking behaviors and perceptions: Results from a knowledge, attitudes, and practices survey, Uganda, 2013.

BACKGROUND: Rabies is a viral disease of animals and people causing fatal encephalomyelitis if left untreated. Although effective pre- and post-exposure vaccines exist, they are not widely available in many endemic countries within Africa. Since many individuals in these countries remain at risk of infection, post-exposure healthcare-seeking behaviors are crucial in preventing infection and warrant examination. METHODOLOGY: A rabies knowledge, attitudes, and practices survey was conducted at 24 geographically diverse sites in Uganda during 2013 to capture information on knowledge concerning the disease, response to potential exposure events, and vaccination practices. Characteristics of the surveyed population and of the canine-bite victim sub-population were described. Post-exposure healthcare-seeking behaviors of canine-bite victims were examined and compared to the related healthcare-seeking attitudes of non-bite victim respondents. Wealth scores were calculated for each household, rabies knowledge was scored for each non-bitten survey respondent, and rabies exposure risk was scored for each bite victim. Logistic regression was used to determine the independent associations between different variables and healthcare-seeking behaviors among canine-bite victims as well as attitudes of non-bitten study respondents. RESULTS: A total of 798 households were interviewed, capturing 100 canine-bite victims and a bite incidence of 2.3 per 100 person-years. Over half of bite victims actively sought medical treatment (56%), though very few received rabies post-exposure prophylaxis (3%). Bite victims who did not know or report the closest location where PEP could be received were less likely to seek medical care (p = 0.05). Respondents who did not report having been bitten by a dog with higher knowledge scores were more likely to respond that they would both seek medical care (p = 0.00) and receive PEP (p = 0.06) after a potential rabies exposure event. CONCLUSIONS: There was varying discordance between what respondents who did not report having been bitten by a dog said they would do if bitten by a dog when compared to the behaviors exhibited by canine-bite victims captured in the KAP survey. Bite victims seldom elected to wash their wound or receive PEP. Having lower rabies knowledge was a barrier to theoretically seeking care and receiving PEP among not bitten respondents, indicating a need for effective and robust educational programs in the country.

Educational Approach to Prevent the Burden of Vaccinia Virus Infections in a Bovine Vaccinia Endemic Area in Brazil.

Bovine vaccinia (BV), caused by Vaccinia virus (VACV), is a zoonotic disease characterized by exanthematous lesions on the teats of dairy cows and the hands of milkers, and is an important public health issue in Brazil and South America. BV also results in economic losses to the dairy industry, being a burden to the regions involved in milk production. In the past 20 years, much effort has been made to increase the knowledge regarding BV epidemiology, etiologic agents, and interactions with the hosts and the environment. In the present study, we evaluated milking practices that could be associated with VACV infections in an endemic area in Brazil and proposed an educational tool to help prevent VACV infections. In our survey, 124 individuals (51.7%) from a total of 240 had previously heard of BV, 94 of which knew about it through BV outbreaks. Although most individuals involved in dairy activities (n = 85/91) reported having good hygiene practices, only 29.7% used adequate disinfecting products to clean their hands and 39.5% disinfected cows' teats before and after milking. Furthermore, 46.7% of individuals reported having contact with other farm and domestic animals besides dairy cattle. We also evaluated the presence of IgG and IgM antibodies in the surveyed population. Overall, 6.1% of likely unvaccinated individuals were positive for anti-Orthopoxvirus IgG antibodies, and 1.7% of all individuals were positive for IgM antibodies. Based on our findings, we proposed educational materials which target individuals with permanent residence in rural areas (mainly farmers and milkers), providing an overview and basic information about preventive measures against VACV infections that could enhance BV control and prevention efforts, especially for vulnerable populations located in endemic areas.

Twenty Years after Bovine Vaccinia in Brazil: Where We Are and Where Are We Going?

Orthopoxvirus (OPV) infections have been present in human life for hundreds of years. It is known that Variola virus (VARV) killed over 300 million people in the past; however, it had an end thanks to the physician Edward Jenner (who developed the first vaccine in history) and also thanks to a massive vaccination program in the 20th century all over the world. Although the first vaccine was created using the Cowpox virus (CPXV), it turned out later that the Vaccinia virus was the one used during the vaccination program. VACV is the etiological agent of bovine vaccinia (BV), a zoonotic disease that has emerged in Brazil and South America in the last 20 years. BV has a great impact on local dairy economies and is also a burden to public health. In this review, we described the main events related to VACV and BV emergence in Brazil and South America, the increase of related scientific studies, and the issues that science, human and animal medicine are going to face if we do not be on guard to this virus and its disease.

Laboratory Infection of Novel Akhmeta Virus in CAST/EiJ Mice.

Akhmeta virus is a zoonotic Orthopoxvirus first identified in 2013 in the country of Georgia. Subsequent ecological investigations in Georgia have found evidence that this virus is widespread in its geographic distribution within the country and in its host-range, with rodents likely involved in its circulation in the wild. Yet, little is known about the pathogenicity of this virus in rodents. We conducted the first laboratory infection of Akhmeta virus in CAST/EiJ Mus musculus to further characterize this novel virus. We found a dose-dependent effect on mortality and weight loss (p < 0.05). Anti-orthopoxvirus antibodies were detected in the second- and third-highest dose groups (5 × 104 pfu and 3 × 102 pfu) at euthanasia by day 10, and day 14 post-infection, respectively. Anti-orthopoxvirus antibodies were not detected in the highest dose group (3 × 106 pfu), which were euthanized at day 7 post-infection and had high viral load in tissues, suggesting they succumbed to disease prior to mounting an effective immune response. In order of highest burden, viable virus was detected in the nostril, lung, tail, liver and spleen. All individuals tested in the highest dose groups were DNAemic. Akhmeta virus was highly pathogenic in CAST/EiJ Mus musculus, causing 100% mortality when ≥3 × 102 pfu was administered.

Re-Emergence of Yellow Fever in Brazil during 2016-2019: Challenges, Lessons Learned, and Perspectives.

Yellow fever (YF) is a re-emerging viral zoonosis caused by the Yellow Fever virus (YFV), affecting humans and non-human primates (NHP). YF is endemic in South America and Africa, being considered a burden for public health worldwide despite the availability of an effective vaccine. Acute infectious disease can progress to severe hemorrhagic conditions and has high rates of morbidity and mortality in endemic countries. In 2016, Brazil started experiencing one of the most significant YF epidemics in its history, with lots of deaths being reported in regions that were previously considered free of the disease. Here, we reviewed the historical aspects of YF in Brazil, the epidemiology of the disease, the challenges that remain in Brazil's public health context, the main lessons learned from the recent outbreaks, and our perspective for facing future YF epidemics.

Absence of YF-neutralizing antibodies in vulnerable populations of Brazil: A warning for epidemiological surveillance and the potential risks for future outbreaks.

Yellow Fever (YF) is an acute febrile illness caused by yellow fever virus (YFV), a mosquito-borne flavivirus transmitted to humans and non-human primates. In Brazil, YF is a public health threat and may cause recurrent epidemics, even with the availability of a vaccine. We evaluated the sero-status for YFV in 581 individuals living in a risk area for YF in Brazil. The area presents history of cases and is located in the southeast region of country where outbreaks of YF have been reported since 2016. Through, a PRNT assay, we found 25.8% of individuals lacking YF-neutralizing antibodies. Furthermore, neutralizing antibodies were not detected in 10 individuals with proven vaccination. Our findings reinforce the importance of surveillance systems and the need of an urgent intensification of immunization programs in regions with YFV circulation. Monitoring susceptible individuals that could act as potential disseminators for YFV in risk areas should also be considered.

Barriers to attendance of canine rabies vaccination campaigns in Haiti, 2017.

We conducted a cross-sectional survey to better understand the barriers to attendance at canine rabies vaccination campaigns in Haiti. A structured community-based questionnaire was conducted over a 15-day period during May-June 2017, focused on socio-economic status correlated with participation at canine rabies vaccination campaigns. Questions phrased as a bidding game were asked to determine individuals' willingness to pay (WTP) for dog rabies vaccination and willingness to walk (WTW) to fixed-point vaccination campaigns. The Kaplan-Meier estimator was applied to determine relationships between survey variables. Logistic regression was used to examine factors associated with participants' WTP and WTW. A total of 748 households from eight communities were surveyed. Respondents were predominantly female (54.4%) and had a median age of 45 years. The total number of owned dogs reported from households was 926, yielding a human-to-dog ratio in dog-owning households of 5.2:1. The majority of dogs (87.2%) were acquired for security, and 49% were allowed to roam freely; 42.0% of dog owners reported that they were unable to manage (or restrain) their dogs using a leash. Seventy per cent of dog owners were willing to pay up to 15.9 gourdes (0.25 USD) and/or walk up to 75 m to vaccinate their dogs. Households that owned free-roaming dogs, owned dogs for the purpose of companionship and owned dogs that they were unable to walk on a leash were associated with a higher WTP for vaccination. Living in Artibonite Department, having a middle or higher household income, and owning a dog for security purpose were associated with a higher WTW for vaccination. Low leash use and propensity for dogs to roam freely are barriers to successful fixed-point vaccination methods in Haiti, and alternative methods such as door to door (DD), capture-vaccinate-release (CVR) or oral vaccination should be explored. There may be some prospect for fee-for-service vaccination in Haiti; however, this programme should be introduced as a supplement, rather than a replacement for free rabies vaccination programmes so that mass dog vaccination is not discouraged.

Circulation of vaccinia virus in southern and south-eastern wildlife, Brazil.

We evaluated 345 wild animals from southern and south-eastern Brazil to understand their role in vaccinia virus (VACV) transmission cycle. VACV DNA was detected in rodents, marsupials, chiroptera and cingulate, expanding the knowledge of VACV host range in wildlife that could potentially act as source of infection in rural and urban areas.

Silent Circulation of the Saint Louis Encephalitis Virus among Humans and Equids, Southeast Brazil.

Saint Louis encephalitis virus (SLEV) is a mosquito-borne flavivirus that occurs throughout the Americas, and is considered a public health threat. In Brazil, SLEV has been detected from human cases associated with dengue-like disease, but no neurological symptoms were reported. Furthermore, the epidemiology of SLEV in human populations is still poorly explored in the country. We reported serological and molecular detection of SLEV in a healthy population of equids and humans from rural areas in Southeast Brazil. A plaque reduction neutralization test was applied, and neutralizing antibodies were detected in 11 individuals (4.6%) and 60 horses (21.5%). A qPCR targeting the 5'UTR region and reverse transcription-PCR (RT-PCR) targeting the non-structural protein (NS5) gene were performed and three individuals tested positive in both assays. Subsequent phylogenetic analysis confirmed SLEV circulation and its findings suggest the occurrence of an asymptomatic or subclinical presence in human and animal cases, correlating with the risks for outbreaks and consequently burden of SLEV infections to public health. Preventive strategies should include improved surveillance in regions with a high probability of SLEV occurrence, improvement in diagnostic methods, and evaluation of exposure/risk factors that can favor SLEV emergence.

The influence of poverty and rabies knowledge on healthcare seeking behaviors and dog ownership, Cameroon.

BACKGROUND: Rabies is a fatal encephalitis caused by lyssaviruses, with most human cases worldwide resulting from rabid dog bites. Although effective animal and human vaccines have been available for over 100 years, control efforts have not been adequately implemented on the global scale and rabies remains one of the greatest global zoonotic threats to human health. We conducted a knowledge, attitudes and practices survey in Northern Cameroon to describe dog ownership characteristics, rates of dog bites, and post-bite healthcare seeking behaviors. METHODS: The survey was performed in four rural Cameroonian communities. A structured community-based questionnaire was conducted over a 20-day period in April 2010, and focused on socio-economic factors correlated with gaps in rabies knowledge. Information pertaining to socio-demographics, as well as attitudes and practices with regard to animal bites and bite treatment practices were recorded. Characteristics of dog ownership such as dog confinement, resources provided to dogs, and dog vaccination status were examined. Human to dog ratios were compared on a linear scale to poverty scores by community. When applicable, 2-tailed Chi-square tests or Fisher's exact tests were calculated to determine relationships between variables. We also used One-way Analysis of Variance (ANOVA) to identify associations between rabies knowledge and wealth with dog ownership, dog vaccination, and human healthcare seeking behaviors. Independent variables were evaluated using multivariate logistic regression analysis. RESULTS: A total of 208 households were enrolled. Respondents were predominantly male (68.3%), with a median age of 43.6 years. Eighty-four households (39.9%) reported owning a total of 141 dogs (human dog ratio 10.4:1). The majority of dogs (61%) were allowed to roam freely. A history of rabies vaccination was reported for 30.8% of owned dogs. Respondents reported 11 bites during the two years preceding the survey (annual bite incidence was 2.6% [95% CI 1.4%- 4.6%]). Only one person (9.1%) received rabies post-exposure prophylaxis (PEP), and none described symptoms of clinical illness consistent with rabies. Respondents who indicated that they would seek medical care and PEP after a dog bite had higher average wealth and rabies knowledge index scores (p = 0.01 and 0.04, respectively). Respondents who indicated that they would seek care from a traditional healer had significantly lower wealth scores, but not significantly different knowledge scores (p < 0.01 and p = 0.49, respectively). CONCLUSIONS: In the communities evaluated, the majority of dogs were allowed to roam freely and had no history of rabies vaccination; factors that favor enzootic transmission of canine rabies virus. We also identified a strong relationship between poverty and dog ownership. Bite events were relatively common among respondents, and very few victims reported utilizing health services to treat wounds. Increased wealth and knowledge were significantly associated with increased likelihood that a respondent would seek medical care and post-exposure prophylaxis. These findings indicate the need for educational outreach to raise awareness of dog rabies and proper prevention measures.

Natural Vaccinia Virus Infection: Diagnosis, Isolation, and Characterization.

Natural infections of Vaccinia virus (VACV)-the prototype species of the Orthopoxvirus genus, from the family Poxviridae and subfamily Chordopoxvirinae-cause an occupational emergent zoonotic disease that is primarily associated with the handling of infected dairy cattle. In humans, VACV infection is characterized by skin lesions, primarily on the hands, and accompanied by systemic symptoms such as fever, myalgia, headache, and lymphadenopathy. The diagnosis of VACV is usually performed according to the methods described for other orthopoxviruses. This unit describes the methods utilized to obtain clinical samples, the serological and molecular techniques used for diagnosis, and the isolation methods and techniques used for molecular and biological characterization of the viruses. © 2016 by John Wiley & Sons, Inc.