On an acute case of Chagas disease in a region under vector control in the state of São Paulo, Brazil

No vector transmitted cases of Chagas disease had been notified in the state of São Paulo since the 1970s. However, in March, 2006, the death of a six-year-old boy from the municipality of Itaporanga was notified to the Center for Epidemiological Survey of the São Paulo State Health Secretariat: an autochthonous case of acute Chagas disease. The postmortem histopathological examination performed in the Hospital das Clínicas of the Botucatu School of Medicine confirmed the diagnosis. Reference to hospital records, consultation with the health professionals involved in the case and interviews with members of the patient's family supplied the basis for this study. We investigated parasite route of transmission, probable local reservoirs and vectors. No further human cases of acute Chagas disease were diagnosed. No locally captured vectors or reservoirs were found infected with Trypanosoma cruzi. Alternative transmission hypotheses - such as the possible ingestion of foods contaminated with vector excreta - are discussed, as well as the need to keep previously endemic regions and infested houses under close surveillance. Clinicians should give due attention to such signs as uni- or bilateral palpebral edema, cardiac failure, myocarditis, pericarditis, anasarca and atypical signs of nephrotic syndrome or nephritis and consider the diagnostic hypothesis of Chagas disease.

A retrospective study of 40 victims of Crotalus snake bites: analysis of the hepatic necrosis observed in one patient

Forty patients with a diagnosis of snake bite were studied at the Infectious and Parasitic Disease Service of the Faculty of Medicine of Botucatu. Thirty were males and 10 females, ranging in age from 16 to 70 years. All were farm laborers and 35 of them were bitten in the lower limbs. Two of the 9 patients seen more than 6 hours after the bite died. The low mortality rate (5%) observed could be explained by the early care provided, by the use of appropriate doses of anti-crotalus serum, parenteral hydration, urine alkalinization with sodium bicarbonate and induction of osmotic diuresis with a mannitol solution. Anatomopathological examination of one of the patients who died revealed extensive hepatic necrosis. The authors discuss the possibility of the effect of a factor of snake venom in the genesis of hepatic necrosis and in the increased transaminase levels.

Use of a condom in sex relations by HIV carriers

The frequency with which condoms are used in sex relations by subjects with HIV was determined by interviewing 132 individuals, 82 men and 50 women, most of them from São Paulo state and some from other regions of the country, all of them seen at an outpatient clinic of the School of Medicine in Botucatu. The women were younger, were of lower educational level and had poorer professional qualification than men. Also, a greater proportion of women were widowed, separated or divorced. We observed that 43.9% of men and 72% of women had been contaminated by the sexual route, but only 41.2% of the men and 31.8% of the women reported the use of a condom after the diagnosis of infection, with most men and women preferring sexual abstinence. The results enable the conclusion that there is still a need to continue to provide information about the use of condoms and to guarantee their free-of-charge distribution due to the low levels of education and professional qualification of the individuals studied. The data also suggest that campaigns for the dissemination of preventive measures should consider the social and cultural differences of infected women.

Diagnosis of hantavirus infection in humans and rodents in Ribeirão Preto, State of São Paulo, Brazil

INTRODUCTION: Hantavirus pulmonary and cardiovascular syndrome (HPCS) is an emerging serious disease in the Americas. Hantaviruses (Bunyaviridae) are the causative agents of this syndrome and are mainly transmitted through inhalation of aerosols containing the excreta of wild rodents. In the Ribeirão Preto region (state of São Paulo, Brazil), HPCS has been reported since 1998, caused by the Araraquara virus (ARAV), for which Necromys lasiurus is the rodent reservoir. This study aimed to show diagnostic results relating to infection in humans and rodents, obtained at the Virology Research Center of the Ribeirão Preto School of Medicine, University of São Paulo, between 2005 and 2008. METHODS: HPCS was diagnosed by means of ELISA and/or RT-PCR in 11 (21.2%) out of 52 suspected cases, and 54.4% of these were fatal. Furthermore, 595 wild rodents (Necromys lasiurus, Akodon sp, Calomys tener and Oligoryzomys sp) were caught between 2005 and 2008. RESULTS: Fifteen (2.5%) of these rodents presented antibodies for hantavirus, as follows: Necromys lasiurus (4%), Calomys tener (1.9%) and Akodon sp (1.5%). Nucleotide sequences obtained through RT-PCR from one HPCS patient and one Calomys tener rodent were compared with hantavirus sequences from GenBank, which showed that both were homologous with ARAV. CONCLUSIONS: This work corroborates previous studies showing that ARAV is the hantavirus causing HPCS in the Ribeirão Preto region. It also shows that rodents infected with hantavirus represent a constant risk of transmission of this virus to man.