Distribution of rotavirus G and P types in north and south Indian children with acute diarrhoea in 1998-99

Rotavirus Gastroenteritis in Eastern Uttar Pradesh, India

OBJECTIVE

To identify cases of rotavirus diarrhea in Uttar Pradesh among children less than 5 y of age presenting with acute gastroenteritis, to study the clinical profile of the cases and to identify the rotavirus genotypes.

METHODS

Any child who is 0-59 mo of age who is admitted to the study facility with diarrhea as the presenting complaint were enrolled into the surveillance after obtaining informed consent. Clinical history and sociodemographic information was recorded for all the patients. Patients with dehydration were treated as per standard protocol. Stool samples were collected for isolation of rotavirus and identification of its genotype.

RESULTS

Of the 418 stool specimens collected, rotavirus was isolated in 47 (11.33%) samples. Rotavirus gastroenteritis was most common below the age of two years. A significant difference in the clinical characteristics between children who were positive for rotavirus and those who tested negative were not observed in this study. But patients with rotavirus diarrhea had longer duration of hospital stay (OR 3.31; CI 1.24-8.87). The outcome was similar in the two groups (OR 2.64; CI 0.27-25.89). G3P[8] was the most common type genotype isolated in 13 (28.89%) patients followed by G2P[4] in 7 (15.56%) patients. Thirteen patients (28.89%) had mixed genotype.

CONCLUSION

Rotavirus diarrhea was most common below two years of age. G3P[8] was the most common genotype identified.

Burden of Rotavirus Diarrhea in Under five Indian Children

NEED AND PURPOSE

Rotavirus is the most common cause of severe diarrhea in infants and young children worldwide. The burden of rotavirus diarrhea in Indian children is not well established. The present study reviewed the epidemiology of rotavirus diarrhea in hospitalized children and in the community, molecular serotyping and under-five mortality caused by rotavirus diarrhea.

METHODS

Publications, reporting rotavirus diarrhea in Indian children, were retrieved through a systematic search of databases including Medline, PubMed, IndMed, websites of WHO, UNICEF, National Family Health Survey, Ministry of Health and Family Welfare, and Government of India. Human studies in English language were included. Age group selected was 0 month to 5 years. No restrictions were applied in terms of study design and time frame.

CONCLUSIONS

Stool sample positivity varied from 4.6% in Kolkata to 89.8% in Manipur, among hospitalized children, and from 4% in Delhi to 33.7% in Manipur in community. Most cases of rotavirus diarrhea in India are caused by G1, G2, and G untypeable strains with distinct regional variations. Rotavirus was identified as an etiological agent in 5.2 to 80.5% cases of nosocomial diarrhea. Data are lacking for rotavirus mortality.

Molecular epidemiology of rotavirus in children and animals and characterization of an unusual G10P[15] strain associated with bovine diarrhea in south India

Rotaviruses are enteric pathogens causing acute, watery, dehydrating diarrhea in various host species, including birds and mammals. This study collected data on the disease burden and strain prevalence of Group A rotavirus in animals and humans in Vellore and investigated interspecies transmission by comparison of circulating genotypes. Stool samples from children aged less than 5 years, admitted to the hospital between January 2003 and May 2006 for diarrhea and diarrheal samples from animals that were collected from a veterinary clinic and several dairy farms near Vellore between February 2007 and May 2008 were processed and subjected to RNA extraction and reverse-transcription PCR for genotyping of VP7 and VP4. Of 394 children with diarrhea, 158 (40%) were positive for rotavirus and the common G types identified were G1 (47, 29.7%), G2 (43, 27.2%), G9 (22, 13.9%), G10 (2, 1.2%), G12 (1, 0.6%) and mixed infections (27, 17.8%). The common P types were P[4] accounting for 57 (36%) samples, P[8] 57 (36%), P[11] 3 (1.8%) and P[6] 2 (1.2%). Of 627 animals, 35 (1 bullock, 2 goats, 32 cows) were found to be infected with rotavirus (5.5%). The common G types identified in order of frequency were G6 (17, 48.5%), G2 (10, 28%), G10 (4, 11%), G8 (2, 5.7%) and mixed infections (2, 5.7%). The common P types were P[6] accounting for 16 (46%) samples, P[4] 7 (20%), P[1] 3 (8.5%) and P[8] 3 (8.5%). An unusual P type P[15] was seen in one sample in combination with G10. The finding of G2 infections which are rarely identified in animals implies anthroponotic transmission since this genotype is predominantly associated with infection in humans.

A systematic review of rotavirus strain diversity in India, Bangladesh, and Pakistan

Of the estimated half-million deaths from rotavirus globally each year, approximately one-third (N = 160,000 deaths) occur in the Indian subcontinent (defined as India, Bangladesh, and Pakistan). Two commercial vaccines are available for use and recommended by WHO, although the prohibitive vaccine price has limited their introduction into routine childhood immunization programs. New rotavirus vaccines are in late clinical development, including two advanced candidates in India. As significant shifts in rotavirus strain diversity have occurred in the past three decades and questions remain regarding whether strain replacement may occur following introduction of rotavirus vaccines, it is important to understand the temporal and regional strain diversity profile before vaccine introduction. We reviewed 33 peer-reviewed manuscripts from the Indian subcontinent and found that the most common G-types (G1-4) and P-types (P[4] and P[8]) globally accounted for three-fourths of all strains in the subcontinent. However, strains varied by region, and temporal analysis showed the decline of G3 and G4 in recent years and the emergence of G9 and G12. Our findings underscore the large diversity of rotavirus strains in the Indian subcontinent and highlight the need to conduct surveillance on a regional scale to better understand strain diversity before and after rotavirus vaccine introduction.

Production of human rotavirus and Salmonella antigens in plants and elicitation of fljB-specific humoral responses in mice

A Nicotiana benthamiana transient expression system was used to express single antigen and dimeric combinations of the human rotavirus (HRV) VP7 and a truncated VP4 (VP4Δ) proteins fused with Salmonella typhimurium's flagellin fljB subunit. Immunoblot analyses using rabbit antibodies generated against these proteins demonstrated that the constructs were successfully expressed with yields ranging from 0.85 to 31.97 μg of recombinant protein per gram of fresh leaf tissue. Expressing the single and dimeric antigens has no effect on plant growth and development except for VP7 and VP4Δ::VP7, which show mild necrotic lesions. Immunization of mice with proteins from leaves transformed with constructs bearing the fljB moiety elicited an fljB-specific humoral response. The Nicotiana benthamiana transient system is efficient to express multiple combinations of pathogen proteins and demonstrates the potential of generating a Salmonella typhimurium subunit vaccine in plants.

Rotavirus types in Europe and their significance for vaccination

The degree of diversity of cocirculating human rotavirus wild-type strains is high. This article reviews the occurrence and frequency of rotavirus types in European children younger than 5 years of age during the past 10-15 years. To enable greater understanding of the overall epidemiologic situation, rotavirus types found in animals in Europe are described. In addition, rotavirus types occurring in children outside Europe are considered. Taken together, these data provide an essential background to the development of rotavirus vaccines. The different concepts of immunization with the 2 main rotavirus candidate vaccines are briefly discussed, and their potential impact on the epidemiology of cocirculating rotavirus wild-type viruses is considered. A case is made for comprehensive surveillance of cocirculating human rotavirus types in Europe after the implementation of rotavirus vaccination.

Epidemiological profile of rotaviral infection in India: challenges for the 21st century

BACKGROUND

Rotaviruses cause acute viral gastroenteritis worldwide. It has been estimated that, each year, 440,000 deaths that occur among children are attributed to rotavirus infection, mainly in developing countries. In India, the diversity of rotaviruses reported during the 1980s and 1990s emphasizes the need for surveillance of cocirculating strains, to follow the rapid changes in circulation and to detect novel strains.

METHODS

We analyzed data from published epidemiological studies, to collate available information on serotyping and genotyping of rotaviruses before the initiation of a national rotavirus surveillance program. The studies included 18 Indian cities and were performed during 1996-2001.

RESULTS

Rotaviruses were detected in 23.4% of patients with diarrhea who presented to the hospital. There were marked geographic differences in virus circulation, with G1 being the single most common G type identified in all parts of India, except for western India. Group B rotaviruses were reported from Kolkata and Pune. Human infections with strains G6, G8, G10, and G9P[19], which may occur as a result of zoonotic transmission of bovine and porcine rotaviruses, were reported from western, southern, and eastern India.

CONCLUSIONS

The remarkable diversity of rotaviruses circulating in India highlights the need for uniform, widespread surveillance for rotaviruses before the initiation and during the implementation of immunization programs.

Serotype diversity and reassortment between human and animal rotavirus strains: implications for rotavirus vaccine programs

The development of rotavirus vaccines that are based on heterotypic or serotype-specific immunity has prompted many countries to establish programs to assess the disease burden associated with rotavirus infection and the distribution of rotavirus strains. Strain surveillance helps to determine whether the most prevalent local strains are likely to be covered by the serotype antigens found in current vaccines. After introduction of a vaccine, this surveillance could detect which strains might not be covered by the vaccine. Almost 2 decades ago, studies demonstrated that 4 globally common rotavirus serotypes (G1-G4) represent >90% of the rotavirus strains in circulation. Subsequently, these 4 serotypes were used in the development of reassortant vaccines predicated on serotype-specific immunity. More recently, the application of reverse-transcription polymerase chain reaction genotyping, nucleotide sequencing, and antigenic characterization methods has confirmed the importance of the 4 globally common types, but a much greater strain diversity has also been identified (we now recognize strains with at least 42 P-G combinations). These studies also identified globally (G9) or regionally (G5, G8, and P2A[6]) common serotype antigens not covered by the reassortant vaccines that have undergone efficacy trials. The enormous diversity and capacity of human rotaviruses for change suggest that rotavirus vaccines must provide good heterotypic protection to be optimally effective.