Pertussis or whooping cough is a highly contagious community disease mainly caused by Bordetella pertussis and B. parapertussis. We report a minor outbreak of whooping cough (2009–2010) in symptomatic subjects from Bisham, near Swat, Khyber Pukhtoonkhawa province, Pakistan. Interestingly, our results show that all the culture-positive isolates (n = 21) collected from children (average age 3·46 years), were identified as B. parapertussis after routine identification tests and PCR IS481, IS1001 and IS1002. Furthermore, in the affected patients, none had received immunization with diphtheria-pertussis-tetanus (DTPw) vaccine. Therefore, the possibility of the re-emergence of the disease due to limitation of basic health services as a result of the political unrest due to the 9/11 situation is also examined. Moreover, we discuss the importance of vaccinating both adults and children with DTPwPaw vaccine containing both organisms for better protection.

A total of 495 diarrhoea and non-diarrhoea patients whose ages ranged between 5 and 39 years were examined for the presence of Campylobacter jejuni, Salmonella and Shigella species. About 12% of the specimens from diarrhoea patients were positive for Campylobacter jejuni compared with 6% and 10% for Salmonella and Shigella species. In contrast 2%, 0% and 1% of the samples from non-diarrhoea patients were positive for Campylobacter jejuni, Salmonella and Shigella species respectively.

Most (62%) of the Campylobacter jejunifrom diarrhoea patients were isolated from children under the age of 10 years. This compared with 26 % and 37 % for Salmonella and Shigella species in this age group. The frequency of isolation of Campylobacter jejuni in diarrhoea patients was highest during the dry months of the year. This study demonstrates the importance of Carnpylobacter jejuni as a major bacterial cause of diarrhoea in this part of the world.

Formalin-fixed samples from 221 animal brains received for rabies diagnosis in Nigeria were digested in 0·1% trypsin in phosphate buffered saline, pH 7·4, and smears stained for rabies antigen by direct immunofluorescence (IF). The results were compared with those obtained using fresh material from the same animals for Negri body staining, mouse inoculation (MI) and occasionally immunofluorescent staining.

From 191 specimens examined for Negri bodies and by mouse inoculation 51 and 64 respectively proved positive. The IF smear technique under investigation failed to detect 5 of these but showed up as positive 30 which had been recorded as Negri-negative and 19 that had gone undetected by MI too. In a direct comparison with IF staining of fresh tissue from 23 known rabies positive animals the similar staining of trypsin-digested formalized smears failed to give a positive result in 2 out of 23 cases.

Some problems were encountered with smears not sticking to slides. When gelatinized slides were used fluorescence was sometimes poorer.

Where transport and refrigeration are difficult and section-cutting equipment is lacking the technique of IF staining of smears prepared from formalized brain tissue after treatment with trypsin can be a useful adjunct to other diagnostic methods. It also makes for safer working where special facilities are absent.

A purified soluble Vi antigen was used in counterimmunoelectrophoresis (CIE), passive haemagglutination (HA) and solid phase radio-immunoassay (SPRIA) for detection of serum Vi antibody. Serum Vi antibody was detected in 13 of 14 chronic typhoid carriers by both CIE and HA. SPRIA studies showed that Vi antibodies in sera of these carriers were mainly of the IgG class. Successful treatment with amoxycillin in one carrier, who initially showed a positive Vi test, resulted in a reversion in 6 months to seronegativity as measured by Vi CIE. However, Vi antibody was also detected in 10 sera (3%) from 329 control subjects by HA but not by CIE. When the CIE assay was applied to 1030 serum specimens obtained from hospitalized patients, it was able to detect one typhoid carrier, but one (0·1%) non-carrier also gave a positive Vi CIE test. It is thus concluded that Vi CIE is more specific and no less sensitive than Vi HA for the detection of the typhoid carrier state. The finding by SPRIA that the anti-Vi antibodies present in typhoid carriers' sera were mainly of the IgG class further justified the use of CIE as a precipitation test for their detection.

The distribution of three putative adhesin genes in 123 Shiga toxin-producing (STEC) strains was determined by PCR. The STEC strains were isolated from human patients (n=90) and food (n=33) and were characterized by serogroup, virulence markers (eae, stx1, stx2) and adherence factors (efa1, lpfAO157, saa) genes. Serogroups O157 (64·4%) and O26 (28·8%) were the most frequent among human strains and the majority (60·6%) of food strains were serologically non-typable. The adhesin genes efa1 (90%) and lpfAO157 (73·3%) were the most common in humans strains and saa (45·5%) in food strains. The presence of these genes in addition to eae in STEC from different sources may suggest a relevant role in their pathogenesis.

A total of 1887 bovine sera positive to the Rose Bengal plate test were subjected to other serological tests for bovine brucellosis: the complement fixation test using warm fixation (CFTW), the serum agglutination test (SAT) and the radioimmunoassay (RIA).

The SAT was generally much less sensitive than the CFTW. Many sera, however, gave positive reactions in the SAT but no reaction in the CFTW or the RIA. These SAT reactions were attributed to IgM antibody.

Comparison between the results of the CFTW and the RIA led to the conclusion that 200 ng could be used as a minimum diagnostic reaction in the RIA.

Mice from Loughborough and Nottingham were obtained in order to compare the inheritance of warfarin resistance in these populations with that established for a Cambridge population (Wallace & MacSwiney, 1976). Using the same breeding programme and warfarin testing technique, it is established that resistance in the new areas is, as in the Cambridge area, controlled by the major resistance gene, War, in chromosome 7, with penetrance affected by sex and modifiers. In addition, survival differences in males of different ages strongly suggests that War + has less penetrance with age. Penetrance differences between the experiments establishes that wild populations differ in their modifier complex and that more than one modifier, probably several, exist. Questions are posed as to the adaptive significance of the phenomena, and the way in which they work, in the patchwork of warfarin baited and unbaited areas in this country.

Antimicrobial resistance (AR) is a growing problem worldwide and international travel, cross-border migration, and antimicrobial use may contribute to the introduction or emergence of AR. We examined AR rates and trends along the US–Mexico border by analysing microbiology data from eight US hospitals in three states bordering Mexico. Microbiology data were ascertained for the years 2000–2006 and for select healthcare and community pathogens including, three Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae) and three Gram-positive (Staphylococcus aureus, Enterococcus, Streptococcus pneumoniae) pathogens and 10 antimicrobial–pathogen combinations. Resistance was highest in S. aureus (oxacillin resistance 45·7%), P. aeruginosa (quinolone resistance 22·3%), and E. coli (quinolone resistance 15·6%); six (60%) of the 10 antimicrobial–pathogen combinations studied had a significantly increasing trend in resistance over the study period. Potential contributing factors in the hospital and community such as infection control practices and antimicrobial use (prescription and non-prescription) should be explored further in the US–Mexico border region.

Antisera prepared in the rabbit by injection of crystalline horse-serum albumin or crystalline human-serum albumin show a considerable diminution in specificity after more than one course of six to eight injections has been given.

The ratio of precipitate nitrogen to antigen nitrogen at the optimal point is smaller in antisera obtained after one course of injections than in antisera derived from subsequent bleedings.

In the case of antisera obtained from first bleedings, the ratio of precipitate nitrogen to antigen nitrogen determined at the optimal point with homologous antigen is of approximately the same value in both the antigen-antibody systems studied. The increase in the values of the ratios for antisera from subsequent bleedings is also the same for both systems.

A questionnaire survey was undertaken to determine the exposure of a study population to campylobacteriosis source risk factors (environmental, water, food) and results were stratified by age, population density and deprivation. Data were gathered using an exposure assessment carried out by telephone in the Grampian region of Scotland. Univariate analysis showed that children aged 5–14 years, living in low population density (0–44·4 persons/km2) and affluent areas had elevated exposure to environmental and water risk factors. Multivariate logistic regression analysis revealed that younger age groups and lower population density were significant indicators for most environmental risk factors. The results compared to reported disease incidence in Grampian showed that greater exposure to risk factors does not necessarily coincide with greater disease incidence for age groups, particularly for the 0–4 years age group. Further research is required to explain the relationship between exposure and disease incidence.

The susceptibility of laboratory reared Zimbabwean Amblyomma hebraeum and A. variegatum ticks to infection with geographically distinct Cowdria ruminantium strains was investigated by feeding both species simultaneously on individual sheep infected with one of the four strains (Crystal Springs [Zimbabwe], Ball 3 [South Africa]. Gardel [Guadeloupe] and Nigeria [Nigeria]). A. hebraeum ticks demonstrated a high susceptibility to infection with all four C. ruminantium strains. In comparison. A. variegatum were less susceptible to infection with the Crystal Springs and Ball 3 strains (P < 0·001), but showed a similar susceptibility to the Gardel and Nigeria strains. The differences in susceptibility of A. variegatum to infection with the four strains of C. ruminantium correlated with the origin of these strains. The consistently higher susceptibility of A. hebraeum ticks to infection with geographically different C. ruminantium strains may be one explanation for the observation that heartwater is a more serious problem where A. hebraeiun is the vector of the disease.

Infection with potential bacterial enteropathogens was studied prospectively in 94 Swedish travellers. Three faecal samples were collected, regardless of diarrhoeal symptoms, after each of three 1-week stays in Singapore, Hong Kong and Japan. The specimens were analysed for salmonella, shigella, yersinia, campylobacter and different enterotoxin-producing bacteria. A potential enteropathogen was identified in 30% (28/94) of the participants, i.e. in 26% of the healthy and in 39% of the travellers with diarrhoea. The most common isolates were enterotoxigenic bacteria of different species (14%), salmonella (11%) and campylobacter (7%). By performing enterotoxin-tests on six different colonies from the primary culture of each specimen enterotoxigenic Escherichia coli (ETEC) as well as enterotoxin-producing Klebsiella sp., Citrobacter sp. and Morganella morganii were identified. The latter strains were as prevalent as ETEC. In the 33 participants with diarrhoea enterotoxigenic bacteria (18%) and campylobacter (18%) were the most common isolates. Campylobacter-infected travellers developed symptomatic disease (6/7) significantly (P>0·02) more often than those infected with salmonella (3/10) or enterotoxigenic bacteria (6/13; 2 ETEC, 4 other species).

During the 3-year period 1985–7, all strains of Shigella sonnei isolated in Catania, Sicily, showed a high level of resistance to trimethoprim (Tp) which was invariably associated with resistance to other antibiotics.

Plasmid analysis showed 18 different electropherotypes: 35 of 37 strains harboured a plasmid of 70 Megadaltons (MDa), and 29 of 37 strains a plasmid of 130 MDa.

Restriction endonuclease fingerprinting of purified 70 MDa plasmid DNA from different strains demonstrated that these plasmids were similar but not identical.

In some strains with transferable Tp resistance, DNA hybridization analysis demonstrated the presence of genes coding for the production of dihydrofolate reductase (DHFR) type V. In contrast, there was no detectable hybridization with DNA probes specific for genes coding for DHFR types I, II and IV. This is the first report of the DHFR type V gene outside Sri Lanka.

Introduction of antiretroviral therapy (ART) has dramatically reduced the incidence of infectious ocular diseases in human immunodeficiency virus (HIV)-infected individuals. However, the effects of long-term ART and chronic HIV infection on the eye are ill-defined. This study determined the occurrence and severity of ocular diseases among 342 participants in a rural South African setting: HIV-naïve (n = 105), HIV-infected ART-naïve (n = 16), HIV-infected on ART for <12 months (short-term ART; n = 56) and HIV-infected individuals on ART for >36 months (long-term ART; n = 165). More HIV-infected participants presented with an external eye condition, in particular blepharitis, than HIV-naïve individuals (18% vs. 7%; age-adjusted odds ratio (aOR) = 2·8, P < 0·05). Anterior segment conditions (particularly keratoconjunctivitis sicca and pterygium) were also more common (50% vs. 27%; aOR = 2·4; P < 0·01). Compared with individuals on short-term ART, participants receiving long-term ART were more likely to have clinically detectable cataract (57% vs. 38%; aOR = 2·2, P = 0·01) and posterior segment diseases, especially HIV retinopathy (30% vs. 11%; aOR = 3·4, P < 0·05). Finally, long-term ART was significantly associated with presence of HIV retinopathy (P < 0·01). These data implicate that ocular disease is more common and of more diverse etiology among HIV-infected individuals, especially those on long-term ART and suggest that regular ophthalmological monitoring of HIV-infected individuals on ART is warranted.

During 9th December 2016 and 12th February 2017, 149-chickenpox cases were reported in a tribal and industrial zone of Rakholi (n = 80) and Surangi (n = 69) villages from Union Territory of India. An epidemiological investigation was performed to assess the characteristics and determinants of the chickenpox outbreak. Overall, the attack rate per 100 population in Rakholi village (n = 1757) was 4.5% and 19.1% in Surangi village (n = 360). Ages of the cases were ranged from 6 months to 55 years and there were 53 females and 96 males. For the laboratory investigations, 25 serum samples, three urine specimens, three throat swabs and six blister/skin swabs were collected from 37-suspected chickenpox cases. Altogether, 30-suspected cases were laboratory confirmed by either IgM EIA or varicella zoster virus (VZV) DNA PCR. Both VZV-specific IgM and IgG antibodies were detected in 19-suspected cases. Two suspected cases showed the presence of VZV-specific IgG antibodies but not IgM antibodies. On the contrary, three suspected cases showed VZV-specific IgM but not IgG antibodies. Overall, 31 of 37-suspected cases (including one equivocal case) were laboratory confirmed. The partial sequencing of ORF-28 gene of VZV revealed circulation of clade-1 viruses. In conclusion, this investigation provides detail information about the chickenpox outbreak in the tribal and industrial setting from India. Furthermore, the study emphasises the need to investigate more chickenpox outbreaks in different parts of India.

The prevalence of sexually transmitted infection (STI) pathogens in Beijing, China, is rarely reported. In this study, 34 911 symptomatic outpatients with suspected genital infections who attended outpatient clinics in a tertiary care hospital were included to investigate the updated prevalence of Ureaplasma urealyticum (UU), Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and herpes simplex virus (HSV) from 1 January 2013 to 31 December 2016 in Beijing, China. Results indicated that a decrease trend (UU, CT, NG and HSV) in male and an increase trend (UU, CT and NG) in female were observed during the period. Patients aged 20–39 years old were mostly affected by these pathogens, while the prevalence in patients aged 20–29 years old was the highest, The prevalence of UU in male was significantly lower than in female (31.5% vs. 49.3%, P < 0.05), while the prevalence of NG in male was significantly higher than in female (2.5% vs. 0.8%, P < 0.05). In patients with co-infections, 60.6% of male and 71.4% of female were co-infected by UU + CT. In total, 11.9% and 88.1% of patients with HSV infections were confirmed to be infected by HSV-1 and HSV-2. This study could contribute to a better understanding of the current epidemiological features of UU, NG, CT and HSV among symptomatic patients attending an outpatient clinic in Beijing, China, and thus facilitate to develop more effective intervention, prevention and treatment of STI.

One of the largest nationwide bursts of the first COVID-19 outbreak occurred in Spain, where infection expanded in densely populated areas through March 2020. We analyse the cumulative growth curves of reported cases and deaths in all Spain and two highly populated regions, Madrid and Catalonia, identifying changes and sudden shifts in their exponential growth rate through segmented Poisson regressions. We associate these breakpoints with a timeline of key events and containment measures, and data on policy stringency and citizen mobility. Results were largely consistent for infections and deaths in all territories, showing four major shifts involving 19–71% reductions in growth rates originating from infections before 3 March and on 5–8, 10–12 and 14–18 March, but no identifiable effect of the strengthened lockdown of 29–30 March. Changes in stringency and mobility were only associated to the latter two shifts, evidencing an early deceleration in COVID-19 spread associated to personal hygiene and social distancing recommendations, followed by a stronger decrease when lockdown was enforced, leading to the contention of the outbreak by mid-April. This highlights the importance of combining public health communication strategies and hard confinement measures to contain epidemics.

Results are presented of the laboratory examination of faeces specimens from 20,273 patients with acute diarrhoea. These were household index cases seen in general practice in a London borough during the years 1953–68. An annual average of about 2% of households in the area were affected, but there was considerable fluctuation with year and season. Half the patients were children although only one-fifth of the population at risk was under 15 years of age. The greatest incidence of diarrhoea was among children under 5 years old. Male children, but female adults predominated.

Specimens were sent for laboratory diagnosis at the discretion of the general practitioner. The laboratory found some abnormality in nearly a third and there were indications that transmissible infection was involved in about one-fifth of patients. The most common diagnosis was Sonne dysentery (9%) which came in epidemic waves and made its greatest impact among young school children. Microscopy was useful, and giardiasis was diagnosed in 1·4% of index patients. Other parasites were less commonly found. Fatty globules characteristic of an infectious condition we have called ‘fatty diarrhoea’ were frequently observed by microscopy in stools from young children and occasionally from older persons. Blood or pus cells were seen in less than half the shigella and salmonella infections and in a much smaller proportion of the remainder. A test for occult blood performed on specimens from all patients of 40 years or older was positive, in the absence of visible red cells, in a tenth of these cases.

Other studies on the bacteriology of diarrhoea in general practice are referred to and some epidemiological comparisons made. The possible place of unidentified infective agents in the aetiology of undiagnosed diarrhoeas and of ‘fatty diarrhoea’ is discussed.

The fungal skin flora of a sample of 205 elderly persons in Alexandria, drawn by cluster sampling probability technique, was investigated. Pathogenic yeasts were isolated from 18·6% and 10·3% of skin and nails respectively. Candida albicans (16·1% and 7·3%) was prominent. A low prevalence of dermatophytes grown on agar (2·4% from skin and 2·9% from nails) was observed. In contrast, saprophytic filamentous fungi comprised 45·4 and 50·7% of skin and nails samples respectively. This study showed no statistically significant effect of sociodemographic variables (sex, marital status, crowding index, and income per capita) on the skin flora. There was no statistical significant difference between elderly diabetics and non-diabetics as regards fungal skin flora.