Effectiveness of Haemophilus influenzae type b conjugate vaccine on radiologically-confirmed pneumonia in young children in Pakistan.

OBJECTIVE: The effectiveness of Haemophilus influenzae type b (Hib) vaccine in preventing severe pneumonia in Asian children has been questioned, and many large Asian countries yet to introduce Hib conjugate vaccine in immunization programs. The primary objective of this study was to assess Hib conjugate vaccine effectiveness (VE) on radiologically-confirmed pneumonia in children born after introduction of Hib conjugate vaccine in Pakistan. STUDY DESIGN: A matched case-control study enrolled cases of radiologically-confirmed pneumonia in several hospitals serving low-income populations during 2009-2011. Cases were matched by age and season with 3 hospital and 5 neighborhood controls. Pneumonia was diagnosed using standardized World Health Organization criteria for chest radiograph interpretation. Matched OR were estimated for VE. RESULTS: A total of 1027 children with radiologically-confirmed pneumonia were enrolled; 975 cases, 2925 hospital controls, and 4875 neighborhood controls were analyzed. The coverage for 3 doses of diphtheria-tetanus-pertussis-hepatitis B-Hib conjugate vaccine was 13.7%, 18%, and 22.7% in cases, hospital controls and neighborhood controls, respectively. Estimated Hib VE for radiologically-confirmed pneumonia was 62% with 3 doses of vaccine using hospital controls and 70% using neighborhood controls. CONCLUSIONS: Hib conjugate vaccine prevented a significant fraction of radiologically-confirmed pneumonia in children in Pakistan. Maximizing impact on child survival needs improved immunization coverage.

A review of hepatitis viral infections in Pakistan.

A review of published literature on viral hepatitis infections in Pakistan is presented. A total of 220 abstracts available in the Pakmedinet and Medline have been searched. All relevant articles were reviewed to determine the prevalence of hepatitis viral infections in Pakistan. Two hundred and three (203) relevant articles/abstracts including twenty nine supporting references are included in this review. Of the articles on prevalence of hepatitis infection, seven were related to Hepatitis A, fifteen to Hepatitis E while the remaining articles were on frequency of hepatitis B and C in different disease and healthy population groups. These included eight studies on healthy children, three on vertical transmission, nineteen on pregnant women, fifteen on healthy individuals, six on army recruits, thirty one on blood donors, thirteen on health care workers, five on unsafe injections, seventeen on high risk groups, five on patients with provisional diagnosis of hepatitis, thirty three on patients with chronic liver disease, four on genotypes of HBV and five on genotypes of HCV. This review highlights the lack of community-based epidemiological work as the number of subjects studied were predominantly patients, high risk groups and healthy blood donors. High level of Hepatitis A seroconversion was found in children and this viral infection accounts for almost 50%-60% of all cases of acute viral hepatitis in children in Pakistan. Hepatitis E is endemic in the country affecting mostly the adult population and epidemic situations have been reported from many parts of the country. The mean results of HBsAg and Anti-HCV prevalence on the basis of data aggregated from several studies was calculated which shows 2.3% and 2.5% prevalence of HBsAg and Anti-HCV in children, 2.5% and 5.2% among pregnant women, 2.6% and 5.3% in general population, 3.5% and 3.1% in army recruits, 2.4% and 3.6% in blood donors, 6.0% and 5.4% in health care workers, 13.0% and 10.3% in high risk groups, 12.3% and 12.0% in patients with provisional diagnosis of hepatitis and 25.7% and 54% in patients with chronic liver disease respectively. This review has illustrated the high endemicity of hepatitis viral infections in Pakistan where hepatitis B and C potentially account for a serious burden of the disease. This review has triggered the launching of a network intervention for the control of hepatitis viral infectious. This review was used as the basis for the launch of hepatitis programme, but putting it into a formal review took time and the hepatitis program was initiated.

Etiology of a suspected measles outbreak: preceding measles reduction activities in Pakistan.

OBJECTIVE: To characterize patients with suspected measles, determine the magnitude of the outbreak in selected areas, and perform laboratory testing on patients with suspected measles to confirm the etiology of the outbreak. STUDY DESIGN: Cross-sectional survey. PLACE AND DURATION OF STUDY: Islamabad and Rawalpindi in June 2006. METHODOLOGY: Survey and specimen collection from households was carried out in areas affected by rash and fever during the outbreak. Teams asked if household members had rash and fever and administered a detailed questionnaire of clinical signs and symptoms for measles for each person who reported a rash and fever episode. A sample of cases with fever, rash, and either cough, conjunctivitis, or coryza was laboratory tested for measles and rubella. RESULTS: Of 2,225 households visited, 284 individuals met the rash and fever case definition. Laboratory testing of eleven blood specimens revealed that the rash and fever outbreak was caused by rubella in 6 and measles in 2 with three equivocal results. CONCLUSION: Laboratory confirmation of suspected measles cases is essential during measles elimination activities in Pakistan and other countries with endemic rubella.