Behavioral-biological surveillance of emerging infectious diseases among a dynamic cohort in Thailand.

BACKGROUND: Interactions between humans and animals are the key elements of zoonotic spillover leading to zoonotic disease emergence. Research to understand the high-risk behaviors associated with disease transmission at the human-animal interface is limited, and few consider regional and local contexts. OBJECTIVE: This study employed an integrated behavioral-biological surveillance approach for the early detection of novel and known zoonotic viruses in potentially high-risk populations, in an effort to identify risk factors for spillover and to determine potential foci for risk-mitigation measures. METHOD: Participants were enrolled at two community-based sites (n = 472) in eastern and western Thailand and two hospital (clinical) sites (n = 206) in northeastern and central Thailand. A behavioral questionnaire was administered to understand participants' demographics, living conditions, health history, and animal-contact behaviors and attitudes. Biological specimens were tested for coronaviruses, filoviruses, flaviviruses, influenza viruses, and paramyxoviruses using pan (consensus) RNA Virus assays. RESULTS: Overall 61/678 (9%) of participants tested positive for the viral families screened which included influenza viruses (75%), paramyxoviruses (15%), human coronaviruses (3%), flaviviruses (3%), and enteroviruses (3%). The most salient predictors of reporting unusual symptoms (i.e., any illness or sickness that is not known or recognized in the community or diagnosed by medical providers) in the past year were having other household members who had unusual symptoms and being scratched or bitten by animals in the same year. Many participants reported raising and handling poultry (10.3% and 24.2%), swine (2%, 14.6%), and cattle (4.9%, 7.8%) and several participants also reported eating raw or undercooked meat of these animals (2.2%, 5.5%, 10.3% respectively). Twenty four participants (3.5%) reported handling bats or having bats in the house roof. Gender, age, and livelihood activities were shown to be significantly associated with participants' interactions with animals. Participants' knowledge of risks influenced their health-seeking behavior. CONCLUSION: The results suggest that there is a high level of interaction between humans, livestock, and wild animals in communities at sites we investigated in Thailand. This study highlights important differences among demographic and occupational risk factors as they relate to animal contact and zoonotic disease risk, which can be used by policymakers and local public health programs to build more effective surveillance strategies and behavior-focused interventions.

Leptospirosis in northeastern Thailand: hypotension and complications.

During an outbreak of leptospirosis in northeastern Thailand, 148 patients with serologically diagnosed leptospirosis were seen in Loei Hospital. The clinical features were consistent with those described for the classic manifestation of the disease. However, hypotension was a common finding: noted in 94 patients (64%) upon admission or early in the course of the disease. Of these hypotensive patients, 64 (68%) had impaired renal function: 30 patients (32%) had prerenal azotemia and 34 (36%) were in renal failure. Pulmonary complications, including pulmonary edema, hemorrhage, ARDS, and interstitial pneumonitis, occurred in 22% of patients and were often associated with renal failure. A clear association existed between hypotension and renal failure and pulmonary complications. The overall mortality rate was 3.4%. The causes of death were pulmonary complications, renal failure, and sepsis. The death rate among patients with complications was 11.6%. Blood exchange, in addition to conventional treatment, was beneficial in severe leptospirosis with complications and hyperbilirubinemia.

Hypotension, renal failure, and pulmonary complications in leptospirosis.

During a recent outbreak of leptospirosis in northeastern Thailand, 148 patients with serologically diagnosed leptospirosis were seen in Loei hospital. The common serotypes were L. pyrogenes, and L. sejroe. Hypotension with a mean arterial pressure less than 70 mmHg upon admission or within 24 h after admission was observed in 94 patients or 64%. 30 patients had normal renal function; 30 patients had prerenal azotemia with mild pulmonary complication in 2; and 34 patients had acute renal failure. 29 patients with acute renal failure had pulmonary complications including pulmonary hemorrhage in 8, pulmonary edema in 3, acute respiratory distress syndrome (ARDS) in 14 and interstitial pneumonitis in 4. 54 patients had normal blood pressure. In this group 5 patients had acute renal failure; 16 had prerenal azotemia and 33 had normal renal function. Interstitial pneumonitis was noted in one patient with prerenal azotemia. Less renal complication and minimal pulmonary complication were seen in leptospirosis patients with normal blood pressure. The patients with normal renal function had no pulmonary complication. Good association existed between hypotension, renal failure and pulmonary complications.