Leptospira interrogans serovar unipertama isolated in Malaysia.

A leptospiral isolate from a bovine kidney was found to be antigenically different from all previously recognized serovars of Leptospira interrogans based on the cross-agglutinin absorption test. The new serovar belongs to the Sejroe serogroup, and the name Leptospira interrogans serovar unipertama is proposed for it, with strain K2-1 as the reference strain.

The bacteriological prevalence of leptospiral infection in cattle and buffaloes in West Malaysia.

A cross-sectional bacteriological survey of cattle in West Malaysia revealed 14.4% (32/222) had leptospiral infection. Isolates were obtained from all except one herd with prevalence of infection in herds ranging from 0-44.8%. A small number of buffalo urine samples were examined and all of them were found to be negative. A leptospiral isolate obtained from a bovine kidney proved to be a new serovar of Leptospira interrogans and the name unipertama was assigned to it. Six other leptospiral serovars were isolated, namely canicola, australis, javanica, ballum, pomona and hardjo. All six serovars were isolated for the first time in cattle in Malaysia. Cattle in Malaysia appear to be the maintenance host for serovar hardjo. The presence of the other serovars in cattle was probably due to contact with the maintenance hosts, pigs for serovar pomona and rodents for the other three serovars. It appears that the epidemiology of leptospiral infection in cattle in Malaysia is similar to that reported overseas.

Pneumonia associated with infection with pneumocystis, respiratory syncytial virus, chlamydia, mycoplasma, and cytomegalovirus in children in Papua New Guinea.

Paired serum samples were collected from 94 children with pneumonia admitted to Goroka Hospital, Papua New Guinea. All but three of the children were aged 1-24 months. Only nine children were malnourished, with weight for age less than 70% of the Harvard median (three had weight for age less than 60% of the Harvard median). Pneumocystis carinii antigen was detected in the serum of 23 children. Twenty two children had serological evidence of recent infection with respiratory syncytial virus. Five children were probably infected with Chlamydia trachomatis at the time of the study, and there was less convincing serological evidence of current infection in a further 11 children. Five children showed a fourfold rise in antibody to Mycoplasma pneumoniae. Although only one child showed a fourfold rise in antibody to cytomegalovirus, 86 children had this antibody. No child showed a fourfold rise in antibody to Ureaplasma urealyticum or Legionella pneumophila. P carinii, respiratory syncytial virus, C trachomatis, M pneumoniae, and cytomegalovirus may be important causes of pneumonia in children in developing countries.

A major outbreak of epidemic polyarthritis in New South Wales during the summer of 1983/1984.

A large outbreak of epidemic polyarthritis (EPA) caused by Ross River virus (RRV) occurred in New South Wales in the summer of 1983/1984. The total number of cases was unknown, but 1196 cases were confirmed by laboratory tests. Most patients came from the area west of the dividing range, with especially large numbers in the Murrumbidgee irrigation area. Cases were reported from October 1983 to June 1984, with 60% of cases occurring in January and February. The seasonal pattern was similar throughout the state. Men and women were affected in approximately equal numbers, with the highest frequencies in the 30-39 years' age group. Clinical illness was uncommon in young children. Based on a detailed study of 118 patients from Griffith, arthralgia, lethargy, rash and headache were the most common symptoms. The average period of incapacity (defined as inability to resume normal duties) was about six weeks. On this basis, the cost of the epidemic was estimated at about $3 million. There were 257 cases of EPA in the Griffith Shire and it was calculated that approximately 340 RRV infections occurred in the shire. The implication is that, in this outbreak, most RRV infections resulted in clinical illness.

Detection of Ross River virus immunoglobulin M antibodies by enzyme-linked immunosorbent assay using antibody class capture and comparison with other methods.

An enzyme-linked immunosorbent assay based on antibody class capture was developed for the detection of Ross River virus-specific immunoglobulin M antibodies (RRV IgM). The assay was specific, reproducible and precise. When compared with conventional tests for the detection of RRV IgM, such as hemagglutination inhibition following sucrose density gradient centrifugation and indirect enzyme-linked immunosorbent assay, the class capture assay was more sensitive. In 186 sera which were collected from 39 patients with RRV infection over a period of 1-4 yr from onset of initial symptoms, RRV IgM persisted for at least 1-2 yr. Sera were tested both at a single dilution from which the results were expressed as a binding index and in a dilution series in which they were expressed as an antibody titre. Binding index values gave better discrimination between sera collected during acute and later phases of the disease and may be of greater value than antibody titres in the diagnosis of RRV infection.

Dengue in the northern region of Queensland, 1981-1982.

During the dengue epidemic in northern Queensland in 1981 and 1982, type I dengue was serologically confirmed in 196 patients (mean age, 32.2 years) from the Cairns district. The most common symptoms were fever (99%), headache (92%), rash (91%), myalgia (93%), skin itching (75%) and arthralgia (60%). Haemorrhagic manifestations were noted in 14 patients. Most only showed skin petechiae. One patient also had bleeding from the gastrointestinal and urinary tracts. No cases of shock were recorded. Leucopenia was present in 57% of patients. A discussion on the relevance of these findings to dengue haemorrhagic fever/dengue shock syndrome is included. A serological survey after the epidemic suggests that approximately 7% of the population have antibodies to dengue as a result of the recent epidemic.

Dengue fever. Reappearance in northern Queensland after 26 years.

During March, 1981, a number of cases of dengue fever occurred in Cairns and Townsville, northern Queensland. From October, 1981, an outbreak of the infection was recognized on Thursday Island and, by May 1982, an estimated 38% of residents had been infected. Isolated cases were reported from other towns in northern Queensland and from other islands in the Torres Strait. Clinical presentation varied from that of severe incapacitating illness lasting up to seven days to infections which were confirmed by serological tests, but were not associated with apparent illness. No deaths were reported. Entomological surveys indicated that the domestic breeding vector of dengue, Aedes aegypti, is widely distributed throughout Queensland - southwards to Dirranbandi and westwards to Mornington Island. In some localities, the indices of Ae. aegypti abundance are alarmingly high, but at least in some suburbs of Townsville, it has been effectively controlled.

Haemorrhagic manifestations with Sindbis infection. Case report.

Sindbis infection in man occurs rarely in Australia. Most recorded cases are either asymptomatic or result in a fever sometimes accompanied by a macular or vesicular rash. This case is of particular interest because of the severe haemorrhagic vesicular rash and the repeated recurrence of symptoms over a 5 month period together with the persistence of IgM antibodies to Sindbis virus.

Epidemic polyarthritis in northeastern Australia, 1978-1979.

In a study of epidemic polyarthritis in central and northern Queensland, clinical disease was observed most frequently in urban-dwelling adult females. Clinical and subclinical infections were detected year round, although the majority of clinical infections occurred between the months of January and June. In the communities studied, there were approximately 50 subclinical infections for each clinical infection. There was no detectable association between any HLA-A or HLA-B phenotypes and epidemic polyarthritis.

Rodent zoonoses in North Queensland: the occurrence and distribution of zoonotic infections in North Queensland rodents.

A study of potentially zoonotic infections was carried out on 351 rodents trapped in north-eastern Queensland. Their ecosystems included towns, agricultural and livestock areas, wookland and rainforest. Nine serotypes of salmonellae were obtained from asymptomatic carries in predominantly settled locations. Two strains of Ps. pseudomallei occurred in rainforest near Innisfail and one on a cattle property adjacent to Townsville. Ps. aeruginosa caused bronchopneumonia in one animal from Townsville harbour. Ifection by leptospirae of six serogroups and seven serovars were identified by serological or cultural examinations. Enzootic foci occurred on the Mount Spec rainforest where celledoni and australis were being excreted by rats adjacent to the Paluma dam system. In addition to the scrub typhus locations at Rocky Creek, Atherton Tableland and Bullocky Creek, near Ingham, which were confirmed, a new focus of infection by R. tsutsugamushi was identified at El Arish near Tully. Water rat (H. chrysogaster) at Townsville harbour constituted a reservoir of toxoplasmosis. In addition to the known human pathogenic helminths H. nana and H. diminuta, localized foci of hookworms (Ancylostoma spp.) were found. Histological evidence of cytomegalic disease of the salivary glands or kidneys was a common finding.