ABSTRACT
A modified adsorption-elution technique for concentration of enteric viruses from sewage and water samples was developed. The viruses in water were concentrated by negatively charged membrane filtration, eluted with 2.9% tryptose phosphate broth containing 6% glycine pH 9.0, and reconcentrated using centrifugation by a speedVac concentrator. The presence of poliovirus, hepatitis A virus (HAV) RNA, and rotavirus antigen was determined by cell culture isolation, nested polymerase chain reaction (nested PCR), and enzyme-linked immunosorbent assay (ELISA), respectively. A total of 100 sewage and water samples were collected from various sources in congested communities in Bangkok, concentrated and examined for those enteric viruses. Of 20 surface water samples from canals which located near sewage drains, 15% were positive for HAV RNA by nested PCR. Of 48 domestic sewage samples from man-holes of underground sewers, 8% were positive for rotavirus antigen by ELISA. Even though the samples were concentrated 256-2,000 fold, poliovirus was not found by isolation in cell culture.
Subject(s)
Animals , Antigens, Viral/analysis , Cell Line , Centrifugation , Enzyme-Linked Immunosorbent Assay , Filtration , Hepatovirus/isolation & purification , Humans , Macaca mulatta , Poliovirus/isolation & purification , Polymerase Chain Reaction , RNA, Viral/analysis , Rotavirus/immunology , Thailand , Tumor Cells, Cultured , Virus Cultivation , Water MicrobiologyABSTRACT
A significant number of acute non A to E hepatitis cases are reported in Thailand every year, and the etiologies of these cases are unknown. Members of the herpesviridae family have been reported to cause either a self limited or fatal hepatitis in a small proportion of patients in other parts of the world. To determine whether herpesviruses may play a role in acute non A to E hepatitis, sera from 32 acute hepatitis patients without markers for acute hepatitis A to E virus infection were examined for IgM to herpesvirus type 2 (HSV-2), cytomegalovirus (CMV), and Epstein-Barr virus (EBV) using commercially available assays. IgM to HSV-2 was detected in four sera, IgM to CMV was detected in one serum, and IgM to EBV was detected in one serum. All of the acute non A to E hepatitis patients recovered and none had underlying conditions associated with impaired immunity. These results suggest that herpesviruses should be considered in the differential diagnosis for Thai patients with hepatitis.
Subject(s)
Acute Disease , Adolescent , Adult , Cytomegalovirus Infections/diagnosis , Female , Hepatitis, Viral, Human/diagnosis , Herpes Genitalis/diagnosis , Herpesviridae Infections/diagnosis , Herpesvirus 2, Human/immunology , Herpesvirus 4, Human/immunology , Humans , Male , Middle Aged , Serologic Tests , ThailandABSTRACT
Hemorrhagic fever (HF) has been widespread in Cambodia and thought to be due to dengue virus although laboratory confirmation has been lacking. Between 1980 and 1995, 49,420 cases of HF and 3,032 deaths were reported. Cases increased during this period; large epidemics of HF occurred every two to three years. In 1995 there were 10,208 cases of HF with 424 deaths. Over a two day period in August 1995, 40 consecutive cases were investigated at the National Pediatric Hospital in Phnom Penh, Cambodia. All 40 cases were confirmed as dengue by virus identification and/or serology. Mean age was 6.5 years. Of 39 patients with complete medical records, the diagnoses were: dengue fever (n = 3), dengue hemorrhagic fever (DHF) grade 2 (n = 21), DHF grade 3 (n = 10), and DHF grade 4 (n = 5). The serologic response was secondary in 95%. Dengue virus was identified in 13 of 40 cases. All four dengue serotypes were identified. The high frequency of secondary infections, the low mean age of admission, and identification of all four dengue serotypes support the national statistics to show that DHF is highly endemic in Cambodia.
Subject(s)
Adolescent , Cambodia/epidemiology , Child , Child, Preschool , Cross-Sectional Studies , Severe Dengue/mortality , Dengue Virus/classification , Developing Countries , Endemic Diseases , Female , Humans , Incidence , Male , Serotyping , Survival AnalysisABSTRACT
To better characterize the etiology of acute non-A, B, C hepatitis, 24 sera from 50 acute hepatitis without acute markers for hepatitis A, B, and C were examined for acute markers for the hepatitis E virus (HEV), cytomegalovirus (CMV), herpes simplex virus type 2 (HSV-2), and Epstein-Barr virus. Immunoglobulin M (IgM) specific for HEV, HSV-2, and CMV was detected using ELISA and total Ig specific to EBV was determined by standard indirect immunofluorescence. IgM to CMV was not observed in sera from any of the patients; whereas, IgM to HEV was detected in sera from 2 patients and IgM to HSV-2 was detected in 5 of 24 acute hepatitis patients. In addition, high titer of antibody was found in 2 of the patients. This results indicate that HSV-2 and HEV circulate in Thailand and are responsible for a small proportion of non-A, B, C hepatitis in Thailand.