Economic Burden of Influenza in Thailand: A Systematic Review.

Thailand has a high incidence and high mortality rates of influenza. This study summarizes the evidence on economic burden or costs of influenza subsequent to the occurrence of influenza illness in the Thai population by specific characteristics such as population demographics, health conditions, healthcare facilities, and/or cost types from published literature. A systematic search was conducted in six electronic databases. All costs were extracted and adjusted to 2018 US dollar value. Out of 581 records, 11 articles (1 with macroeconomic analysis and 10 with microeconomic analyses) were included. Direct medical costs per episode for outpatients and inpatients ranged from US$4.21 to US$212.17 and from US$163.62 to US$4577.83, respectively, across distinct influenza illnesses. The overall burden of influenza was between US$31.1 and US$83.6 million per year and 50-53% of these estimates referred to lost productivity. Costs of screening for an outbreak of influenza at an 8-bed-intensive-care-unit hospital was US$38242.75 per year. Labor-sensitive sectors such as services were the most affected part of the Thai economy. High economic burden tended to occur among children and older adults with co-morbidities and to be related to complications, non-vaccinated status, and severe influenza illness. Strategies involving prevention, limit of transmission, and treatment focusing on aforementioned patients' factors, containment of hospitalization expenses and quarantine process, and assistance on labor-sensitive economy sectors are likely to reduce the economic burden of influenza. However, a research gap exists regarding knowledge about the economic burden of influenza in Thailand.

Three-year experience with 4-site intradermal booster vaccination with rabies vaccine for postexposure prophylaxis.

For booster vaccination of previously immunized persons with potential exposure to rabies, the World Health Organization recommends 2 doses of cell-culture vaccine administered intramuscularly or intradermally on days 0 and 3. We believe that four 0.1-mL intradermal booster doses given on a single day could be used at no risk to the recipient. We studied use of a single booster vaccination on day 0 followed by four 0.1-mL intradermal doses of cell-culture rabies vaccines, and we determined that this is a safe, convenient, and economical regimen for postexposure treatment of previously vaccinated individuals.

Failure of multiple-site intradermal postexposure rabies vaccination in patients with human immunodeficiency virus with low CD4+ T lymphocyte counts.

Human immunodeficiency virus (HIV)-infected patients with low CD4(+) T lymphocyte counts had a poor neutralizing antibody response to pre- and postexposure rabies vaccination. This study of HIV-infected patients with CD4(+) T lymphocyte counts < 200/microL indicated that patients had a poor response after 4-site intradermal vaccinations (4-4-4-0-2-2, doubling the intradermal doses of cell-culture rabies vaccine).

Failure of pre- and postexposure rabies vaccinations in a child infected with HIV.

We report the case of a 6-y-old HIV-infected girl with severe immune deficiency who failed to respond to intramuscular pre-exposure rabies vaccination using human diploid cell rabies vaccine on days 0, 7 and 28. She also failed to respond to an intradermal postexposure rabies regimen using purified verocell rabies vaccine at 4 sites on days 0, 3 and 7 and at 2 sites on days 30 and 90 (double the usual regimen). Sequentially monitored rabies neutralizing antibody titers were below the WHO minimum acceptable level (> 0.15 IU/ml) in all specimens. Rabies prevention in HIV-infected persons with severe immune suppression requires further study.

Exchange transfusion in severe falciparum malaria: a simple method modified from hemodialysis circuit.

We set up a simple extracorporeal circuit, modified from the extracorporeal method generally used in conventional hemodialysis, for exchange transfusion. Temporary vascular access was used in exchange transfusion for both draining the infected blood and infusion of the freshly non-infected blood. This method of exchange transfusion was performed in 3 severe complicated falciparum malaria patients who had a percentage of parasitemia of 80, 40, and 35. The magnitude of parasitemia decreased immediately to less than one per cent and this value persisted twenty-four hours after the procedure. No complications of exchange transfusion were detected in all patients. Erythrocyte morphology determined by scanning electron microscopy was unaltered by exchange transfusion. Because of the simplicity, the effectiveness, and the safety of the procedure, this extracorporeal circuit modified from hemodialysis circuit would be a more beneficial exchange transfusion method in the treatment of severe complicated falciparum malaria than the manually-performed one.

Renal failure in vibrio vulnificus infection.

Vibrio vulnificus infection with septicemia is a life threatening disease in the immunocompromised hosts. Renal involvement has not been documented. We reported herein 8 patients with V. vulnificus septicemia. All were immunocompromised hosts. Four patients had cirrhosis of the liver, 3 were heavy alcohol drinkers and one had systemic lupus erythematosis. Presenting symptomatology included fever, chills, leg pain and skin rash. Renal failure was observed in 6 patients. Four patients died shortly after admission. Two survived with clinical course of tubular necrosis. Renal failure is therefore common in V. vulnificus infection. This should be brought to attention, and vigorous antibiotic treatment is required. The disease may be confused with leptospirosis, scrub typhus, malaria and other forms of sepsis which also present with renal failure.

Immunogenicity of rabies postexposure booster injections in subjects who had previously received intradermal preexposure vaccination.

BACKGROUND: Preexposure rabies vaccination is recommended using the full dose intramuscular or less expensive reduced dose intradermal method. The reliability of the reduced dose intradermal preexposure regimen is still controversial. The objective of this study was to determine whether it will mount a predictable accelerated immune response after a simulated rabies exposure. METHOD: One hundred and thirty-eight veterinary students received intradermal or intramuscular preexposure vaccination using a potent batch of purified chick embryo rabies vaccine. They then received booster injections one year later. RESULTS: Subjects who received intradermal rabies preexposure vaccination, using 0.1 mL of a potent tissue culture vaccine on days 0, 7, and 28, had a lower postexposure booster antibody response 1 year later than subjects given the preexposure series intramuscularly. A significant number showed an unsatisfactory early anamnestic response. Residual neutralizing antibodies, 1 year after the intramuscular preexposure series, were also significantly higher in the intramuscular than in the 0.1 mL dose intradermal group. However, all study subjects had antibody titers above the minimum recommended level of 0.5 IU/mL by day 14. CONCLUSIONS: We conclude that not all subjects who received an intradermal preexposure vaccine series may be fully protected during the first 5 days after an exposure. Rabies immune globulin, injected into bite wounds and followed by a complete postexposure vaccine series, may be indicated if such a patient experiences a severe rabies exposure.

Melioidosis, an environmental and occupational hazard in Thailand.

Melioidosis is a tropical environmental hazard that causes acute and chronic pulmonary disease, abscesses of the skin and internal organs, meningitis, brain abscess and cerebritis, and acute fulminant rapidly fatal sepsis. It is more common among adults, individuals with diabetes, and individuals with chronic renal disease, but it can occur in normal hosts and children. Burkholderia pseudomellei is the most prevalent cause of community-acquired pneumonia, liver and splenic abscess, and sepsis in northeastern Thailand. Melioidosis can reactivate years after primary infection and result in chronic or acute life-threatening disease. With increasing worldwide travel and migration, patients may present in nonendemic countries with reactivation melioidosis decades after leaving an endemic region. We discuss seven selected patients presenting with this disease to a tertiary care facility in Bangkok between 1995 and 1997. Awareness should allow early diagnosis and treatment, which can lead to decreased morbidity and mortality.

Antibody response after a four-site intradermal booster vaccination with cell-culture rabies vaccine.

The current World Health Organization recommendation for booster vaccination of previously immunized individuals with potential exposure to rabies is two doses of vaccine intramuscularly or intradermally on days 0 and 3. We report responses to two types of postexposure treatment of healthy individuals who had received preexposure rabies vaccination 1 year previously. Group A individuals received four intradermal doses (one-fifth of the diluent volume of vaccine per dose) on day 0, and group B individuals received two intramuscular doses on days 0 and 3. Immunogenicity of the two booster regimens was assessed by titrating the amount of neutralizing antibody (Nab). We found that the booster doses of vaccine produced remarkable responses in all subjects. Nab titers of > or = 0.5 IU/mL (acceptable antibody level for protection against rabies) were detected in all subjects on day 14, and they were shown to be consistently high 1 year after the booster vaccination. We also found that the Nab titers for group A were significantly higher (two- to eightfold) than those for group B on days 5, 14, 150, and 360 after the initial booster vaccination (P < .05). Our study shows that the four-site intradermal booster regimen with use of one-fifth of the diluent volume of cell-culture rabies vaccine on day 0 is associated with a significantly higher antibody response than is the conventional booster regimen for subsequent postexposure rabies treatment of individuals who have received preexposure rabies vaccination with cell-culture rabies vaccine 1 year previously.

Edwardsiella tarda bacteremia and septic arthritis in a patient with diabetes mellitus.

Edwardsiella tarda is an uncommon pathogen in the family Enterobacteriaceae which usually infects patients with underlying diseases. Its habitats include fresh water, a variety of animals and human feces. We report a case of E. tarda bacteremia and septic arthritis with underlying diabetes mellitus, the first found in Thailand.

Interleukin-7 induces anti-Mycobacterium avium activity in human monocyte-derived macrophages.

To examine the modulatory role of interleukin (IL)-7 on intracellular growth of Mycobacterium avium complex (MAC), human macrophages were treated either before or after MAC infection with different concentrations of IL-7. At 100 pg/mL, 1 ng/mL, and 10 ng/mL, treatment with IL-7 before infection stimulated secretion of tumor necrosis factor-alpha (TNF-alpha) from MAC-infected macrophages (increase up to 40%) and resulted in dose-dependent reduction in the number of intracellular bacteria. Pretreatment with IL-7 did not inhibit the secretion of transforming growth factor-beta1 (TGF-beta1). IL-7 added to the macrophage monolayer 4 h after infection resulted in both the secretion of TNF-alpha from MAC-infected macrophages (up to 90% increase, P < .05) and antimycobacterial activity (up to 50% reduction in bacteria, P <.05); however, TGF-beta1 production was not inhibited. IL-7-dependent anti-MAC activity of macrophages was inhibited by anti-human TNF-alpha antibody. These results suggest that IL-7 may contribute to the regulation of the immune response against MAC.

Failure of postexposure treatment of rabies in children.

Five failures of postexposure treatment of rabies in small children with multiple severe bites on the face and head are discussed. All had received rabies immune globulin and a potent tissue-culture vaccine. However, not all wounds had been infiltrated with immune globulin. Surgical closure prior to wound injection with immune globulin was performed in three cases. Another patient had wounds sutured after an intramuscular injection of immune globulin, without wound infiltration.

Value of skin testing for predicting reactions to equine rabies immune globulin.

The high cost of postexposure prophylaxis for rabies is one reason that treatment is inadequate in developing countries. This problem has kindled interest in the use of equine rabies immune globulin, which is a less expensive, yet effective, substitute for human rabies immune globulin. Fatal anaphylaxis is a feared complication of the administration of heterologous serum; therefore, authoritative sources recommend prior skin testing. However, recommendations for methods of administering such a skin test and for its interpretation vary greatly. We embarked on a long-term study to develop guidelines for administration and interpretation of skin test results and to eventually determine a cost-benefit ratio. The skin test is not predictive of serum sickness. Anaphylaxis is rare with modern purified and pepsin-digested equine rabies immune globulins. We consider a skin test to be positive only if a wheal of > 10 mm in diameter, with or without flare, or a wheal of 5-10 mm in diameter with a flare of > 20 mm develops. Long-term studies will be required to answer the remaining questions regarding test criteria and cost benefits.

Efficacy study of a new albumin-free human diploid cell rabies vaccine (Lyssavac-HDC, Berna) in 100 severely rabies-exposed Thai patients.

A newly developed human diploid cell rabies vaccine (Lyssavac-HDC), produced without added serum albumin and with an effort to remove the virus-inactivating beta-propriolactone prior to addition of the gelatin, L-cysteine and potassium phosphate stabilizer, was tested for safety immunogenicity, adverse reactions and efficacy in 100 severely rabies-exposed Thais. All patients also received human rabies immune globulin and vaccine was administered using the conventional 5-dose intramuscular schedule of one dose on days 0, 3, 7, 14 and 28. One hundred percent of a subgroup of 40 subjects, where blood had been collected, had neutralizing antibodies greater than 0.5 IU ml-1 on days 28 and 90 and all had detectable titers on days 7, 14, 28, 90, 180 and 360. All patients could be followed for at least 1 year and remained well. No significant side-effects from this vaccine were noted.

Immunogenicity of purified duck embryo rabies vaccine (Lyssavac-N) with use of the WHO-approved intradermal postexposure regimen.

The World Health Organization (WHO) has recommended the following regimen for administration of intradermal postexposure rabies vaccines (tissue or avian cultures): 0.1 mL of the vaccine given intradermally at two sites on days 0, 3, and 7 and at one site on days 28 and 90. WHO did not specify which types of vaccines should be used when following this regimen. We evaluated the efficacy of purified duck embryo rabies vaccine (Lyssavac-N) under the above regimen conditions; although purified duck embryo rabies vaccine is highly immunogenic when given intramuscularly, it differs significantly from the other rabies vaccination products in that it is not a solution, but rather, a suspension with an added preservative. Lyssavac-N was found to produce lower mean neutralizing antibody titers with the WHO-recommended intradermal regimen. However, when the volume of each dose was increased from 0.1 mL to 0.2 mL and the same schedule of administration was followed, satisfactory titers were obtained. We concluded that the WHO intradermal postexposure rabies vaccine regimen should only be used with vaccines that have been subjected to immunogenicity studies with satisfactory results.