Prevalence of antibodies against hepatitis A and E viruses among rural populations of the Chaco region, south‐eastern Bolivia

Souto

Mem. Inst. Oswaldo Cruz

et al. 2002

We investigated the seroprevalence of hepatitis A virus (HAV) and hepatitis E virus (HEV) infection in subjects living in the community of Manguinhos, Rio de Janeiro, Brazil, and assisted Key words: hepatitis A virus -hepatitis E virus -seroprevalence -epidemiology -Rio de Janeiro -Brazil Viral hepatitis is a public health problem worldwide. Two of the agents that cause viral hepatitis are enterically transmitted: hepatitis A virus (HAV) and hepatitis E virus (HEV).In the last years, improvements in environmental sanitation and hygienic conditions, such as piped water and sewage system, have been responsible for a decrease in the endemicity level of hepatitis A in several developing countries. In Brazil, although hepatitis A is considered an endemic disease (Pannuti et al. 1985, Abuzwaida et al. 1987, Bensabath et al. 1987, Queiroz et al. 1995, data published in recent investigations carried out in the State of Rio de Janeiro revealed a shift in the hepatitis A epidemiological pattern. Improvements in life standards of some urban populations are responsible for a decrease in antibody prevalence among children and adolescents (Vitral et al. 1998a,b).HEV infection is quite common in some geographic areas like India, Africa and Southeast Asia, where it can represent the main cause of acute hepatitis (Arankalle et al. 1995 reported in these areas (Shakhgildyan et al. 1986, CDC 1987, Belyakov et al. 1990, Zuang 1992. On the other hand, epidemiological investigations in non-endemic areas show a low, but constant presence of anti-HEV antibodies (about 1.2%) in normal human populations (Balayan et al. 1996, Psichogiou et al. 1996, Irshad 1999.In 1986, the occurrence of outbreaks of HEV infection in the Americas was recognized in Mexico (Velazquez et al. 1990). More recently, two acute cases of hepatitis E were described in Argentina (Schlauder et al. 2000). In Brazil, outbreaks of hepatitis E have never been reported, although some authors found antibodies in some population groups (Focaccia et al. 1995, Parana et al. 1997, Souto & Fontes 1998, Trinta et al. 2001.Nowadays, hepatitis A can be prevented by active immunoprophylaxis and, for a better control of infection, it is necessary to investigate its current prevalence in different areas. On the other hand, further data are needed in order to evaluate the importance of HEV infection in our country. The aim of the present study was to evaluate the prevalence of HAV and HEV infections in an area where sanitary conditions were improved over the last few years. MATERIALS AND METHODSCalculation of sample size -The minimum sample size was estimated using the formula: n = Z² P Q / d², considering as n = estimated sample size; Z = reduced variable, which value is 1,96 when alpha = 0,05; P (estimated prevalence) = probability to achieve the studied phenomenon; Q (1-P) = complement of the estimated prevalence; d (desired precision) = margin of error.

Section: Discussioncontrasting

confidence: 99%

“…The highest anti-HEV IgG prevalence observed in the oldest age groups is according to results found in previous investigations (Balayan et al 1996, Alvarez-Muñoz et al 1999, Bartolini et al 1999. The anti-HEV IgG prevalence according to sex, shows a higher rate among the male group.…”

Section: Discussionsupporting

confidence: 79%

Seroepidemiological markers of enterically transmitted viral hepatitis A and E in individuals living in a community located in the North Area of Rio de Janeiro, RJ, Brazil

Souto

Mem. Inst. Oswaldo Cruz

et al. 2002

“…A study carried out by Bartoloni et al (1999) with rural populations in Bolivia showed a seroprevalence ranging from 4.4 to 10.4 % with no significant differences between genders. In Peru, although data regarding seroprevalence in general population do not exist, anti-HEV IgG was detected in 10.5% of the subjects comprising a risk group (Vildosola et al 2000).…”

Section: Seroprevalence In Humans and Pigsmentioning

confidence: 93%

Molecular Epidemiology of Hepatitis E Virus (Hev) in South America: Current Status

Mirazo¹,

Ramos²,

Arbiza³

2012

VR&R

Hepatitis E virus (HEV) is a common causative agent of acute hepatitis in many developing countries where standards of sanitation and hygiene are poor. HEV is transmitted primarily by the fecal-oral route. However, zoonotic trasmission from animal reservoirs to human by consumption of raw or undercooked meat has also been suggested. In endemic areas, HEV infection occurs as large waterborne epidemics and/or small outbreaks. Sporadic cases of HEV infection have also been reported in developed countries, where its occurrence is not always associated with travel to highly endemic areas. HEV mammalian isolates are classifi ed into four genotypes 1-4, which appear to have a specifi c host range and geographical distribution. The epidemiology of HEV in South America seems to be complex and seroprevalence in human and domestic pigs diff ers both among populations within the same countries and between countries. Additionally, HEV strains have been detected and molecularly characterized and genotype 3 is the most frequently genotype found in the region. Moreover, except for two strains isolated from autochthonous cases of acute hepatitis that occurred in Venezuela and belonged to genotype 1, all sequences detected in South America were classifi ed as within genotype 3. Our understanding of HEV epidemiology has undergone major changes in recent years and despite the fact that several attempts to shed light over the epidemiology of this infection have been carried out in South America, data about the molecular characterization of HEV isolates is still lacking and further investigation is needed. This review summarizes the current status of HEV molecular epidemiology from a regional point of view.

“…This global decline in HAV endemicity has been observed mainly in countries with a human development index (HDI) >0.58 or a water coverage rate >55%. Since 2005, only three Latin American countries (Argentina, Panama, and Uruguay) have introduced [2][3][4]. HAV vaccinations into their routine immunization programs.…”

Section: Introductionmentioning

confidence: 99%

“…The observed seroprevalence in 5-year-old children ranged from high-medium to low [Bartoloni et al, 1989[Bartoloni et al, , 1999Gandolfo et al, 2003]. In addition, over the last few decades, Bolivia has experienced improvement in education, health, and income according to the HDI, which increased from 0.596 in 1990 to 0.729 in 2007.…”

Section: Introductionmentioning

confidence: 99%

Prevalence of Immunity against Infection of Hepatitis A and Hepatitis B in Children Cochabamba, Bolivia

Mr¹,

Masuet-Aumatell²,

Ramon-Torrell³

et al. 2016

J Infect Dis Ther