Assessing the sensitivity of surveillance for pneumonia in rural Thailand.

We conducted a household survey among Sa Kaeo residents to characterize self-reported health-seeking behavior for pneumonia and the proportion of individuals who seek care at a hospital to determine the coverage of a surveillance system. A 2-stage cluster sample was used to select households. A case of pneumonia was defined as a self-reported history of cough and difficulty breathing for at least 2 days or being given a diagnosis of pneumonia by a healthcare provider in the 12-month period beginning February 1, 2002, and ending January 31, 2003. Interviewers administered a structured questionnaire that asked about clinical illness and utilization of healthcare services. Among 1,600 households, 5,658 persons were surveyed, of whom 62 persons met the case definition. Of the 59 persons with complete data, 53 (90%, 95% CI: 79-96) sought medical care and 47 (80%, 95% CI: 67-89) sought care at a hospital facility in the province. Neither distance nor cost was reported as a barrier to seeking care. Most individuals with self-reported pneumonia sought care at the hospital level. Population-based surveillance can provide reliable estimates of hospitalized, chest radiograph-confirmed pneumonia in Sa Kaeo if adjustments are made to account for the proportion of individuals who access a hospital where radiologic assessment is available.

A household survey to assess the burden of influenza in rural Thailand.

Little is known about the disease burden of influenza in middle-income tropical countries like Thailand. The recent outbreak of avian influenza (H5N1) and studies on influenza from neighboring countries highlight the need for data on incidence, access to care, and health care cost. In May/ June 2003, we conducted a province-wide household survey using two-stage cluster sampling to determine the burden of influenza-like illness in Sa Kaeo Province. We used the total number of reported influenza that occurred in May 2003 and a prospective study of outpatient influenza in clinic patients to develop an estimate of the annualized incidence of influenza. Of 718 subjects, 16 (2.2%) suffered an episode of influenza-like illness in the preceding month; 14 sought care, of whom 7 went to a hospital facility. Fifty percent reported missing on average 3 days of work or school. The total individual cost per illness episode was 663 baht (15.78 US dollars). The proportion of outpatients with influenza-like illness caused by an influenza virus in May was 16% and the annualized influenza incidence was estimated to be 5,941/100,000 in Sa Kaeo Province. This survey adds to information indicating that in rural Thailand, the burden of influenza is substantial and costs associated with an illness episode are up to 20% of an average monthly income.

Trends in liver cancer, Sa Kaeo Province Thailand.

OBJECTIVE: To determine liver cancer trends in Sa Kaeo Province, Thailand. METHODS: Death certificate (1993-2003) and hospital records (1999-2003) were reviewed and compared to national averages and other provinces. RESULTS: According to data from death certificates, liver cancer mortality in Sa Kaeo Province increased from 3.1 to 26.1 per 100,000 population between 1993 and 2003. In Thailand overall rates increased from 9.0 to 19.8 per 100,000 population between 1996 and 2003. According to electronic hospital records, the total number of patient encounters (in-patient admissions and out-patient visits) for liver cancer in the two main hospitals in Sa Kaeo Province increased 56% (14% annually) between 1999 and 2003. The number of cases of hepatocellular carcinoma increased from 42 in 2001 to 73 in 2003, while the number of cases of cholangiocarcinoma showed little change. CONCLUSIONS: Thailand as a whole and Sa Kaeo Province specifically have a high burden of liver cancer, which appears to have increased substantially in the past 10 years. Demonstrating the impact of ongoing strategies aimed at reducing risk factors for liver cancer, such as universal hepatitis B vaccination of infants, will require reliable data describing liver cancer disease burden and etiology. Rapid investigations using available data from death certificates, electronic admissions records, and patient charts can provide valuable insights on disease burden and trends.

An outbreak of leptospirosis, Thailand--the importance of the laboratory.

The reported incidence of leptospirosis increased 30-fold in Thailand between 1995 and 2000. Despite many hypotheses to explain the increase, the true etiology remains unknown. We conducted a review of the national surveillance system for leptospirosis, examining the reporting practices, system attributes, and utilization of laboratory confirmation in two northeastern provinces. Using standard guidelines for evaluation of public health surveillance systems, we assessed the timeliness, completeness, and accuracy of data; the sensitivity and specificity of case ascertainment; and the overall usefulness of the Thai leptospirosis surveillance system. Physicians were interviewed to assess compliance and understanding of the case definition. Capacity for confirmation of leptospirosis by a Thai latex agglutination test was assessed. Completeness for variables critical for linking epidemiologic and laboratory data for leptospirosis was 69%. Twenty-eight percent of 208 provincial surveillance reports were considered timely. Interviewed physicians indicated that the national case definition was difficult to understand and apply, and that laboratory confirmation was infrequently used. Compared to a standardized microscopic agglutination test (MAT) panel, the Thai test was specific, but relatively insensitive. We found that a lack of a standardized case definition for leptospirosis, the infrequent use of confirmatory laboratory testing, and the inability to link clinical, epidemiologic, and laboratory data hindered system utility. This surveillance system for leptospirosis highlights difficulties with surveillance of febrile illnesses in general, and the importance of laboratory confirmation for infections that are difficult to diagnose clinically.

Early containment of severe acute respiratory syndrome (SARS); experience from Bamrasnaradura Institute, Thailand.

BACKGROUND: On March 11, 2003, a World Health Organization (WHO) physician was admitted to Bamrasnaradura Institute, after alerting the world to the dangers of severe acute respiratory syndrome (SARS) in Vietnam and developing a fever himself. Specimens from the first day of his admission were among the first to demonstrate the novel coronavirus, by culture, reverse transcription-polymerase chain reaction (RT-PCR), and rising of specific antibody, but proper protective measures remained unknown. The authors instituted airborne, droplet and contact precautions from the time of admission, and reviewed the efficacy of these measures. MATERIAL AND METHOD: A specific unit was set up to care for the physician, beginning by roping off an isolated room and using a window fan to create negative pressure, and later by constructing a glass-walled antechamber, designated changing and decontamination areas, and adding high-efficiency particulate air (HEPA) filters. The use of personal protective equipment (PPE) was consistently enforced by nurse managers for all the staff and visitors, including a minimum of N95 respirators, goggles or face shields, double gowns, double gloves, full head and shoe covering, and full Powered Air Purifying Respirator (PAPR) for intubation. To assess the adherence to PPE and the possibility of transmission to exposed staff a structured questionnaire was administered and serum samples tested for SARS coronavirus by enzyme-linked immunosorbent assay (ELISA). Exposure was defined as presence on the SARS ward or contact with laboratory specimens, and close contact was presence in the patient's room. RESULTS: The WHO physician died from respiratory failure on day 19. 112 of 129 exposed staff completed questionnaires, and the 70 who entered the patient's room reported a mean of 42 minutes of exposure (range 6 minutes-23.5 hours). 100% reported consistent handwashing after exposure, 95% consistently used a fit-tested N95 or greater respirator, and 80% were fully compliant with strict institutional PPE protocol. No staff developed an illness consistent with SARS. Serum samples from 35 close contacts obtained after day 28 had a negative result for SARS coronavirus antibody. CONCLUSIONS: Hospitalization of one of the earliest SARS patients with documented coronavirus shedding provided multiple opportunities for spread to the hospital staff, but strict enforcement of conservative infection control recommendations throughout the hospitalization was associated with no transmission.

Pneumonia surveillance in Thailand: current practice and future needs.

We reviewed reported pneumonia cases and deaths in Thailand since 1975 to evaluate the pneumonia surveillance system. In Sa Kaeo Province, we analyzed 3 years in detail (1999--2001) from electronic surveillance data, and compared deaths reported through surveillance to death certificate data in 1999 and 2000. In addition, we interviewed surveillance personnel who collected the data from all 7 hospitals and from a 10% random sample of health centers. Since the mid-1980s, reported illnesses and deaths from pneumonia have been increasing. In Sa Kaeo, an average of 925 pneumonia cases were reported each year, for an estimated average annual incidence of 211 per 100,000. The age-specific incidence peaked at 1,418 per 100,000 in children less than 5 years. In 1999 and 2000, there were 7 and 6 pneumonia deaths, respectively, reported through the surveillance system, compared with 28 and 53, respectively, reported by death certificate. Sixty-two (82%) of the 72 surveillance personnel reported receiving some training, but most of this was informal. Although written criteria to diagnose pneumonia were established in 1996, those who report cases did not know these criteria. A combination of physician, nurse, and public health workers diagnoses were used. According to the written criteria, cases of suspect or rule out pneumonia should be reported, but when asked about specific examples only 79% of persons interviewed said they would report "tuberculosis with pneumonia" and 44% would report "bronchitis, rule out pneumonia." Seventy-four percent of persons interviewed completed the surveillance report within one day of patient admission.