The aetiology of acute hepatitis in Zimbabwe

Predictors of human-infective RNA virus discovery in the United States, China, and Africa, an ecological study

Background

The variation in the pathogen type as well as the spatial heterogeneity of predictors make the generality of any associations with pathogen discovery debatable. Our previous work confirmed that the association of a group of predictors differed across different types of RNA viruses, yet there have been no previous comparisons of the specific predictors for RNA virus discovery in different regions. The aim of the current study was to close the gap by investigating whether predictors of discovery rates within three regions-the United States, China, and Africa-differ from one another and from those at the global level.

Methods

Based on a comprehensive list of human-infective RNA viruses, we collated published data on first discovery of each species in each region. We used a Poisson boosted regression tree (BRT) model to examine the relationship between virus discovery and 33 predictors representing climate, socio-economics, land use, and biodiversity across each region separately. The discovery probability in three regions in 2010-2019 was mapped using the fitted models and historical predictors.

Results

The numbers of human-infective virus species discovered in the United States, China, and Africa up to 2019 were 95, 80, and 107 respectively, with China lagging behind the other two regions. In each region, discoveries were clustered in hotspots. BRT modelling suggested that in all three regions RNA virus discovery was better predicted by land use and socio-economic variables than climatic variables and biodiversity, although the relative importance of these predictors varied by region. Map of virus discovery probability in 2010-2019 indicated several new hotspots outside historical high-risk areas. Most new virus species since 2010 in each region (6/6 in the United States, 19/19 in China, 12/19 in Africa) were discovered in high-risk areas as predicted by our model.

Conclusions

The drivers of spatiotemporal variation in virus discovery rates vary in different regions of the world. Within regions virus discovery is driven mainly by land-use and socio-economic variables; climate and biodiversity variables are consistently less important predictors than at a global scale. Potential new discovery hotspots in 2010-2019 are identified. Results from the study could guide active surveillance for new human-infective viruses in local high-risk areas.

Funding

FFZ is funded by the Darwin Trust of Edinburgh (https://darwintrust.bio.ed.ac.uk/). MEJW has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 874735 (VEO) (https://www.veo-europe.eu/).

Hepatitis B serological markers and plasma DNA concentrations

Objectives:

To examine hepatitis B (HBV) serological markers and plasma DNA concentrations in a large group of untreated HBV/HIV-coinfected individuals in two sub-Saharan settings.

Design:

Baseline analysis of a randomized controlled trial.

Methods:

DART was a large trial of treatment monitoring practices in HIV-infected adults with advanced disease starting antiretroviral therapy at centres in Kampala or Entebbe, Uganda (n = 2317) and Harare, Zimbabwe (n = 999). HBV serological markers [antibody to HBV core antigen, HBV surface antigen (HBsAg), antibody to HBV surface antigen, HBV ‘e’ antigen (HBeAg), and antibody to hepatitis B ‘e’ antigen] and plasma HBV DNA viral load were measured retrospectively on stored baseline samples. Logistic regression was used to examine associations with baseline demographic and clinical factors.

Results:

The rate of HBsAg positivity was significantly higher in Zimbabwe than Uganda (12.2 vs. 7.7%, adjusted odds ratio = 1.54, P < 0.001) despite a similar prevalence of antibody to HBV core antigen (56.3 vs. 52.4%) in the two settings. Overall, HBsAg positivity was associated with male sex (adjusted odds ratio = 1.54, P < 0.001) but not with age, WHO disease stage, or CD4⁺ cell count. HBeAg was detected among 37% of HBsAg-positive patients, with higher rates among those with advanced WHO stage (P = 0.02). Also in HBsAg-positive patients, HBV DNA was undetectable in 21%, detectable but below the level of quantification in 14%, and quantifiable in 65%. A total of 96% of HBeAg-positive and 70% of HBeAg-negative patients had detectable HBV DNA; 92 and 28% of patients, respectively, had HBV DNA viral load more than 2000 IU/ml.

Conclusion:

High rates of HBV coinfection were observed, highlighting the importance of ensuring that coinfected patients receive an antiretroviral regimen, whether first-line or not, that is active against both viruses.

Predicting acute viral hepatitis serum markers (A and E) in patients with suspected acute viral hepatitis attending primary health care centers in Baghdad: a one year cross-sectional study

BACKGROUND

Viral hepatitis is an important preventable infectious disease with various rates of occurrence in different areas of the world. The main objective of the present study was to evaluate the role of some risk factors in predicting a positive acute viral hepatitis marker among patients with suspected acute viral hepatitis in a primary health care setting in Baghdad. Besides, finding out the occurrence of jaundice, contribution of viruses A and E to the cases that have occurred in Baghdad province was also searched for.

METHODS

Over a period of 1 year a descriptive cross sectional study was carried out at the primary health care centers in Baghdad. A questionnaire form was used to collect data about demographic factors and the results of the investigations. Total serum bilirubin and bilirubin in urine were done at the primary health care center laboratory. The rest of the sera samples were sent to Hepatitis referral Lab at Central Public Health Laboratory (CPHL) to be tested for anti HAV IgM and anti HEV IgM using ELISA technique.

RESULTS

A total of 7,576,372 consultations to primary health care centers were recorded in Baghdad. Among those a total of 2,692 cases (35.5 per 100,000 consultations) were labeled as acute viral hepatitis cases. A positive hepatitis viral marker (A, B, C and E) was found in 1,332 cases (17.6 per 100,000 consultations). More than two fifths (44.8%) of cases were positive for anti-HAV antibodies and another 1.6% had positive anti-HEV antibodies.

CONCLUSION

During 1 year period, the rate of occurrence of suspected acute viral hepatitis cases was 35.5 per 100000 of consultations to the primary health care centers in Baghdad. Of the total suspected cases, only 17.6 per 100000 of the consultations were positive for one of the viral hepatitis markers. Those who tested positive for one of the viral hepatitis markers represent 49.5% of the suspected cases. Proportion of anti HAV IgM positive tests among suspected cases was 44.8%. Factors that were able to predict positive Anti HAV IgM were (younger age group, negative history of cupping or tattooing, negative past history of jaundice). Male gender was the least important predictor of a positive case for anti HAV IgM. Proportion of Anti HEV IgM positive tests among suspected cases was 1.6%. Of the factors studied, only age was able to predict a positive Anti HEV IgM in those more than 15 years. Further studies are recommended.

Molecular characterization of hepatitis B virus isolates from Zimbabwean blood donors

Hepatitis B virus (HBV) is endemic in Africa, being hyperendemic in sub-Saharan Africa. Genotypes A, D, and E circulate in Africa, showing a distinct geographical distribution. The aim of the present study was to determine the HBV genotype distribution in blood donors from different geographical locations in Zimbabwe. Using a restriction fragment polymorphism assay, sequencing of the basic core promoter/precore region and of the complete S open reading frame showed that 29 HBV isolates from geographically distinct regions belong to subgenotype A1. The complete genome of two of these Zimbabwean HBV isolates was sequenced. Forty-four percent of the Zimbabwean HBV isolates (11/23) were characterized by a G1862C missense mutation, which causes a Val to Leu amino acid substitution at position 17 of the precore region. The majority of Zimbabwean HBV isolates clustered with a number of South African HBV isolates, with which they shared characteristic amino acids in the preS1, preS2, and polymerase spacer regions. The wide distribution of subgenotype in Africa, as well as the high intragroup divergence and the geographical clustering of the African and Asian subgenotype A1 HBV isolates indicate that this subgenotype has a long period of endemicity in these regions.

Outbreak of enterically-transmitted hepatitis due to hepatitis A and hepatitis E viruses

BACKGROUND/AIMS

One hundred and eleven patients with acute hepatitis and 61 controls were investigated for hepatitis serological markers in order to determine the viral etiology of cases involved in a waterborne epidemic of hepatitis observed in 1993 in Djibouti, Republic of Djibouti (East Africa). These cases occurred both in indigenous Djiboutians, and in French soldiers and their families in Djibouti. A retrospective study of the viral etiology of acute hepatitis cases observed in French soldiers and relatives living in Djibouti during the 3-year period preceding the epidemic was also undertaken.

METHODS

HAV, HBV and HCV infections were investigated using commercial ELISA tests. HEV infections were investigated by testing IgG and IgM-specific antibodies by means of three different ELISA tests using recombinant proteins or synthetic peptides.

RESULTS

Hepatitis A was observed in 37 (33%) and hepatitis E in 43 (39%) of the 111 cases of acute hepatitis recorded during this epidemic. Hepatitis B represented only 6% of the indigenous cases and hepatitis C was not observed among the cases investigated. Anti-HEV IgG antibodies were also detected in 19% of the indigenous control group.

CONCLUSION

These results suggest that both HAV and HEV were responsible for this waterborne epidemic of acute hepatitis. However, HAV and HEV infections were not equally distributed between French expatriates and Djibouti residents. Whereas HAV infections were mainly observed in French patients, HEV was almost exclusively found in indigenous patients. This study reports for the first time a waterborne outbreak of acute hepatitis simultaneously due to HAV and HEV.

Etiology of acute sporadic hepatitis in adults in Senegal and Tunisia

Markers for acute hepatitis A, B, C and E virus infections were examined in the sera of 72 patients suffering from acute hepatitis in Senegal and Tunisia. Hepatitis B was responsible for 36% and hepatitis C for 21% of the cases. Acute hepatitis A was not diagnosed. HEV infection was not observed in Senegal and represents only 4% of the acute hepatitis cases in Tunisia.

The aetiology of acute viral hepatitis in the western region of Saudi Arabia

Of the 1050 sera of acute viral hepatitis patients admitted to the Infectious Diseases Hospital in Jeddah, Saudi Arabia, over a one-year period, 40.9% were due to hepatitis A, 21.5% to hepatitis B, and 37.6% to non-A, non-B (NANB) hepatitis. The mean age for hepatitis A patients was 4 +/- 2.4 years, with no sex preponderance. The mean ages for hepatitis B and NANB were 26.1 +/- 11.9 and 28.8 +/- 14.2 years, respectively. A male to female ratio of 2:1 was noticed for both. 10% of HBsAg patients were positive for anti-delta. 32% of NANB cases were excluded on the bases of possessing specific IgM against cytomegalovirus (CMV), herpes simplex virus (HSV), Epstein-Barr virus (EBV) or Treponema pallidum. Only 9% of NANB cases had a history of blood transfusion. In conclusion, nearly all cases of acute jaundice in Saudi children are due to hepatitis A, whereas hepatitis B and NANB generally occur in adults. Other viruses such as CMV, HSV, and EBV are highly prevalent and must be excluded in all cases of NANB hepatitis.

[HB virus infection and delta surinfection in Sahelian Africa]

78 hospitalized patients were selected when presenting with at least one of these signs: hepatomegaly, jaundice, ascites, oesophageal varices, abdominal venous pattern, splenomegaly. All had radioimmunoassays for hepatitis B surface antigen (HBsAg) and antidelta antibody (78/78). Acute or chronic hepatic disease was diagnosed in 56 patients: 7 acute viral hepatitis, 13 chronic hepatitis, 23 non alcoholic hepatic cirrhosis, and 13 hepatocellular carcinoma. Twenty-two patients with other diagnoses served as controls. Serum antidelta was present in each group: acute viral hepatitis (2/7), chronic hepatitis (2/13), non alcoholic hepatic cirrhosis (9/23), hepatocellular carcinoma (3/13), controls (2/22). Every patient with acute or chronic hepatic disease and positive serum anti-delta was positive for serum HBsAg. Amony controls, 2 patients with positive serum antidelta were negative for serum HBsAg but positive for antiHBs. Delta superinfection is present in the sahelian region; Patients with acute viral hepatitis, chronic hepatitis, non alcoholic hepatic cirrhosis, and hepatocellular carcinoma are electively infected. Patients with acute or chronic hepatitis and positive serum antidelta have hepatitis B virus evolutive infection (positive serum HBsAg).