Modelling the epidemic spread of an H1N1 influenza outbreak in a rural university town.

Knowledge of mechanisms of infection in vulnerable populations is needed in order to prepare for future outbreaks. Here, using a unique dataset collected during a 2009 outbreak of influenza A(H1N1)pdm09 in a university town, we evaluated mechanisms of infection and identified that an epidemiological model containing partial protection of susceptibles best describes H1N1 dynamics in a rural university environment. We found that the protected group was over 14 times less susceptible to H1N1 infection than unprotected susceptibles. Our estimates show that the basic reproductive rate, R 0, was 5·96 (95% confidence interval 5·83-6·61), and, importantly, R 0 could be decreased to below 1 and similar epidemics could be avoided by increasing the proportion of the initial protected group. Moreover, several weeks into the epidemic, this protected group generated more new infections than the unprotected susceptible group, and thus, such protected groups should be taken into account while studying influenza epidemics in similar settings.

Epidemiological survey of rheumatic heart disease among school children in the Shimla Hills of northern India: prevalence and risk factors.

STUDY OBJECTIVE: To determine the prevalence of rheumatic heart disease (RHD) and study the relationship of this disease to factors such as age, sex, housing, and socioeconomic status in Shimla town and the adjoining rural area. DESIGN: A cross sectional survey, carried out by a specially trained examiner in cardiology. SETTING: The study involved high risk school children (5-16 years of age) from Shimla town and the adjoining rural area of Kasumpti-Suni Block in the period 1992-93. SUBJECTS: A total of 15,080 children on the school register (8120 boys and 6960 girls) were examined generally and specifically for evidence of RHD. MAIN RESULTS: Of the 15,080 children screened, the prevalence of rheumatic fever (RF)/RHD was 2.98 per thousand with no significant difference between the age groups of 5-10 and 11-16 years or in either sex (p > 0.05). The prevalence was significantly greater in rural schools (4.8/1000) than in urban schools (1.98/1000) (p < 0.05). There was overcrowding and poor housing in most cases. There were fewer cases of RHD with severe valvular lesions in the younger age group than in the older children. The mitral valve was the valve most commonly affected by RF/RHD. CONCLUSIONS: RHD continues to be a serious health problem. Regular surveys are needed to identify cases early and to ensure secondary prophylaxis with penicillin is given thereby preventing recurrence of RF and progression of the severity of the valvular lesion. Echocardiography is necessary to identify cases of RF/RHD. Strategies for preventing RHD should involve primary prevention to avert the first attack of carditis and strengthening of secondary prophylaxis through improved education and motivation of patients, parents, and physicians.

Problems and prospects of a traditional source of potable water in hilly terrains.

During epidemic investigation, water sources were tested for quality for drinking purpose. Out of 30 khatris tested, water of 86.7% khatris was fit for human consumption and fecal coliform was not found in any of them. Modification of these khatris was stressed by respondents.

Intestinal parasitism in Himachal Pradesh.

A total of 1629 cases were included in the study for the presence of intestinal parasites during 12 mobile camps in different areas of Himachal Pradesh. 47.08% were positive for parasites. The prevalence rate of helminthic parasites was 32.41% and that of protozoal parasites was 20.81%. The parasitic prevalence has been discussed in the light of peculiar geographical situation of the area.

Synthesis and biological activity of some new furan quaternary salts.

A series of new N-(5-substituted 2-furfuryl)-N,N-dimethyl-N-aryloxyalkyl quaternary ammonium salts relating to general structure IV has been synthesized by reacting 5-substituted 2-(N,N-dimethylaminomethyl)furans IIa-d with appropriate aryloxyalkyl bromides III. The resulting compounds are tested for in vitro antimicrobial activity. A simpler synthesis of 5-nitro-2-(N,N-dimethylaminomethyl)furan (IId) involving the reduction of N,N-dimethyl-5-nitro-2-furamide (Ib) with diborane is described. A new compound, 5-bromo-2-(N,N-dimethylaminomethyl)furnan (IIc), is prepared in a similar way. Many of these compounds (22, 28, 34, 37-42, 44, and 45) indicate high activity against Staphylococcus aureus, Streptococcus faecalis, Klebsiella pneumoniae, and Pseudomonas aeruginosa and are more active than nitrofurantoin, Compounds 22, 34 and 41 exhibit the highest in vitro antibacterial activity in the series. Some of these quaternary salts (22, 25, 37, 37-41, and 60) possess appreciable activity against Mycobacterium tuberculosis H37Rv. None of these compounds show significant antifungal activity. Eight compounds (18, 21, 22, 26-28, 32, and 34) have high in vitro antibacterial activity were inactive when tested for anthelmintic activity in rats against Nippostrongylus brasiliensis and Hymenolepis nana.

Antimicrobial agents: synthesis and antimicrobial activity of new aryloxyalkyl esters of p-hydroxybenzoic acid.

Several new aryloxyalkyl esters of p-hydroxybenzoic acid were synthesized and screened for in vitro antimicrobial activity. Although a few compounds showed low antifungal activity, many possessed appreciable in vitro antibacterial activity. However, none of these compounds was active against Mycobacterium tuberculosis (H37Rv).