Jim Gray

Bio: Jim Gray is an academic researcher from Health Protection Agency. The author has contributed to research in topics: Rotavirus & Norovirus. The author has an hindex of 60, co-authored 132 publications receiving 10158 citations. Previous affiliations of Jim Gray include Public Health England.

Longitudinal study of infectious intestinal disease in the UK (IID2 study): incidence in the community and presenting to general practice

Abstract: OBJECTIVES: To estimate, overall and by organism, the incidence of infectious intestinal disease (IID) in the community, presenting to general practice (GP) and reported to national surveillance. DESIGN: Prospective, community cohort study and prospective study of GP presentation conducted between April 2008 and August 2009. SETTING: Eighty-eight GPs across the UK recruited from the Medical Research Council General Practice Research Framework and the Primary Care Research Networks. PARTICIPANTS: 6836 participants registered with the 88 participating practices in the community study; 991 patients with UK-acquired IID presenting to one of 37 practices taking part in the GP presentation study. MAIN OUTCOME MEASURES: IID rates in the community, presenting to GP and reported to national surveillance, overall and by organism; annual IID cases and GP consultations by organism. RESULTS: The overall rate of IID in the community was 274 cases per 1000 person-years (95% CI 254 to 296); the rate of GP consultations was 17.7 per 1000 person-years (95% CI 14.4 to 21.8). There were 147 community cases and 10 GP consultations for every case reported to national surveillance. Norovirus was the most common organism, with incidence rates of 47 community cases per 1000 person-years and 2.1 GP consultations per 1000 person-years. Campylobacter was the most common bacterial pathogen, with a rate of 9.3 cases per 1000 person-years in the community, and 1.3 GP consultations per 1000 person-years. We estimate that there are up to 17 million sporadic, community cases of IID and 1 million GP consultations annually in the UK. Of these, norovirus accounts for 3 million cases and 130,000 GP consultations, and Campylobacter is responsible for 500,000 cases and 80,000 GP consultations. CONCLUSIONS: IID poses a substantial community and healthcare burden in the UK. Control efforts must focus particularly on reducing the burden due to Campylobacter and enteric viruses.

Detection by PCR of eight groups of enteric pathogens in 4,627 faecal samples: re-examination of the English case-control Infectious Intestinal Disease Study (1993–1996)

Abstract: The English case-control Infectious Intestinal Disease Study (1993-1996) failed to detect an enteric pathogen or toxin in 49% of cases of gastroenteritis. In the present study, polymerase chain reaction (PCR) assays were applied to DNA and cDNA generated from 4,627 faecal samples from cases and controls archived during the original study for the detection of norovirus, rotavirus, sapovirus, Campylobacter spp., Salmonella spp., enteroaggregative Escherichia coli, Cryptosporidium spp., and Giardia spp. The percentage of archived samples from cases and from controls in which at least one agent (or toxin) was detected increased from 53% in the original study to 75% and from 19 to 42%, respectively, after the application of PCR assays. Among cases, the following percentages of enteric pathogens were detected: norovirus 36%, rotavirus A 31%, sapovirus 4%, Salmonella spp. 6%, Campylobacter jejuni 13%, Campylobacter coli 2%, other Campylobacter spp. 8%, enteroaggregative E. coli 6%, Giardia spp. 2%, and Cryptosporidium spp. 2%. The present study provides additional insight into the aetiology of infectious intestinal disease in England and highlights the occurrence of viral infections in cases as well as in asymptomatic individuals. Other notable findings include the frequent presence of Campylobacter spp. other than C. jejuni or C. coli, the high frequency of multiple agents in 41% of cases and in 13% of controls, and the variation in the aetiology and rate of infection found for different age groups. The results demonstrate the greater sensitivity of PCR-based methods compared to current conventional methods.

Molecular Characterization of VP6 Genes of Human Rotavirus Isolates: Correlation of Genogroups with Subgroups and Evidence of Independent Segregation

Abstract: A reverse transcription-PCR (RT-PCR) was established to amplify a 379-bp cDNA fragment (nucleotides 747 to 1126, coding for amino acids 241 to 367) of the VP6 gene of group A rotaviruses associated with subgroup (SG) specificity. Thirty-eight human rotavirus strains characterized with SG-specific monoclonal antibodies were subjected to VP6-specific RT-PCR, and PCR amplicons were used for sequencing. Nucleic acid sequencing and phylogenetic analysis of the VP6 amplicons revealed two clusters, or genogroups. Two genetic lineages were distinguished within genogroup I, consisting of strains serologically characterized as SG I, and three genetic lineages were distinguished within genogroup II, composed of strains serologically characterized as SG II, SG I + II, and SG non-I, non-II. Subgrouping of rotaviruses by means of serological methods may result in strains not being assigned the correct SG or in a failure of strains to subgroup. Molecular characterization of the SG-defining region of VP6 provided evidence for independent segregation of the rotavirus genes encoding VP4, VP6, and VP7.

Foodborne Illness Acquired in the United States—Major Pathogens

Abstract: Estimates of foodborne illness can be used to direct food safety policy and interventions. We used data from active and passive surveillance and other sources to estimate that each year 31 major pathogens acquired in the United States caused 9.4 million episodes of foodborne illness (90% credible interval [CrI] 6.6–12.7 million), 55,961 hospitalizations (90% CrI 39,534–75,741), and 1,351 deaths (90% CrI 712–2,268). Most (58%) illnesses were caused by norovirus, followed by nontyphoidal Salmonella spp. (11%), Clostridium perfringens (10%), and Campylobacter spp. (9%). Leading causes of hospitalization were nontyphoidal Salmonella spp. (35%), norovirus (26%), Campylobacter spp. (15%), and Toxoplasma gondii (8%). Leading causes of death were nontyphoidal Salmonella spp. (28%), T. gondii (24%), Listeria monocytogenes (19%), and norovirus (11%). These estimates cannot be compared with prior (1999) estimates to assess trends because different methods were used. Additional data and more refined methods can improve future estimates.

The severe acute respiratory syndrome.

Abstract: The severe acute respiratory syndrome (SARS) is responsible for the first pandemic of the 21st century. Within months after its emergence in Guangdong Province in mainland China, it had affected more than 8000 patients and caused 774 deaths in 26 countries on five continents. It illustrated dramatically the potential of air travel and globalization for the dissemination of an emerging infectious disease and highlighted the need for a coordinated global response to contain such disease threats. We review the cause, epidemiology, and clinical features of the disease.

Foodborne Illness Acquired in the United States

Abstract: To the Editor: The updated estimates of foodborne illness in the United States reported by Scallan et al. probably overestimate the occurrence of illness caused by unspecified agents because they did not account for the apparent sensitivity of the population survey to the occurrence of norovirus (1,2). The number of illnesses attributed to unspecified agents was derived from the simultaneous processes of extrapolation and subtraction: extrapolation from the population survey to create a base of diarrheal illnesses and subtraction of known agents from this base. Scallan et al. averaged illness rates from 3 successive population surveys to come up with a rate of 0.6 episodes of acute gastroenteritis per person per year. However, the individual rates were 0.49 (2000–2001), 0.54 (2002–2003), and 0.73 (2006–2007). The 2006–2007 survey was conducted at the time of widespread norovirus activity. The estimated rate of population illness was strongly correlated with the number of confirmed and suspected norovirus outbreaks reported to the Centers for Disease Control and Prevention Foodborne Disease Outbreak Surveillance System during each of the survey periods (300, 371, and 491, respectively; R2 = 0.97, p<0.0001). No other known agents were correlated with the population survey rates, and the total numbers of outbreaks were inversely correlated with the population survey data. The strength of the correlation between norovirus outbreaks and survey results suggests that the population survey is sensitive to norovirus activity and that norovirus may account for much of what is considered to be unspecified. The fact that the highest observed population rate was ≈50% greater than the lowest rate suggests that annual variation in norovirus activity may account for a considerable proportion of what otherwise seems to be unspecified. More thorough and timely investigation and reporting of outbreaks could facilitate the development of models to evaluate the number of illnesses and update them annually.

Rotavirus and Severe Childhood Diarrhea

Abstract: Studies published between 1986 and 1999 indicated that rotavirus causes ≈22% (range 17%–28%) of childhood diarrhea hospitalizations. From 2000 to 2004, this proportion increased to 39% (range 29%–45%). Application of this proportion to the recent World Health Organization estimates of diarrhea-related childhood deaths gave an estimated 611,000 (range 454,000–705,000) rotavirus-related deaths.