Pertussis in the Association of Southeast Asian Nations: epidemiology and challenges.

Pertussis is a highly infectious respiratory disease caused by Bordetella pertussis. Infants and young children are particularly at risk of severe and life-threatening disease. Infectious older individuals may transmit Bordetella pertussis to unprotected infants. Pertussis control measures have even failed in some countries with high pertussis vaccination coverage rates, leading to increased incidence rates. In 2014, this caused the World Health Organization to declare pertussis resurgent in some countries and led to recommendations regarding pertussis surveillance and national immunization programs. Despite the resurgence of pertussis, epidemiology of the disease in Southeast Asia has received little attention. In this narrative review, we describe pertussis surveillance systems, control measures, epidemiologic trends, and region-specific pertussis research in Southeast Asia. We also make recommendations for the intensification of pertussis surveillance and research in the region.

Seroepidemiology of Dengue Virus Infection in HIV-Infected Children in Comparison to Healthy Children.

BACKGROUND: Dengue infection is the most common arboviral infection in the world while the HIV/AIDS epidemic remains a global concern. The pathogenesis of both diseases is rather on the contrary and it is generally observed that dengue diseases are uncommon in children with AIDS. OBJECTIVE: To study the seroprevalence of dengue virus infection in HIV-infected children compared to healthy children. MATERIAL AND METHOD: A cross-sectional seroprevalence of dengue virus was conducted at King Chulalongkorn Memorial Hospital, Bangkok, Thailand. Eighty-six HIV-infected children aged less than 15 years and one hundred age-matched healthy children were enrolled. HIV-infected children were classified in categories by CDC 1994 criteria. Neutralizing antibodies to all four dengue serotypes (DEN1, DEN2, DEN3, and DEN4) were measured by plaque reduction neutralization test (PRNT). RESULTS: Fifty out of 86 (58%) HIV-infected children and 65 out of 100 (65%) healthy, HIV-negative children had positive neutralizing antibody against dengue virus by PRNT There were no significant differences between these two groups (p > 0.05). Most children had neutralizing antibody against DEN2. In HIV-infected children, a monotypic PRNT50 pattern was found in 26 children (30%) and multitypic pattern was found in 24 children (28%). Most children had neutralizing antibody against DEN2. There were no significant differences in dengue seroprevalence between these two groups. CONCLUSION: HIV-infected children and healthy children had no different seroepidemiology of dengue virus infection.

Dengue hemorrhagic fever and the kidney.

Dengue virus infection (DVI)/dengue hemorrhagic fever (DHF) is a common febrile illness with a variety of severities. The mortality rate is high in dengue shock syndrome (DSS), caused by circulatory failure due to plasma leakage resulting in multi-organ failure. However, acute kidney injury (AKI) is rarely reported. In areas of endemic DVI, the prevalence of AKI due to DVI has been reported to be as high as 6.0 % in children with AKI, and 0.9 % in children with DVI who were admitted to a hospital. The mechanism of AKI in DVI is not clear. It may result from (a) direct injury as in other infectious diseases, (b) an indirect mechanism such as via the immune system, since DHF is an immunological disease, or (c) hypotensive DSS, leading in turn to reduced renal blood supply and renal failure. The mortality rates of DF/DHF, DSS and DHF/DSS-related AKI are <1 %, 12-44 %, and >60 %, respectively. Kidney involvement is not actually that rare, but is under-recognized and often only reported when microscopic hematuria, proteinuria, electrolyte imbalance, or even AKI is found. The prevalence of proteinuria and hematuria has been reported as high as 70-80 % in DVI. A correct diagnosis depends on basic investigations of kidney function such as urinalysis, serum creatinine and electrolytes. Although DVI-related renal involvement is treated supportively, it is still important to make an early diagnosis to prevent AKI and its complications, and if AKI does occur, dialysis may be required. Fortunately, in patients who recover, kidney function usually completely recovers as well.

Serum Aminotransferases in Thai Children With Dengue Infection.

BACKGROUND: Hepatic manifestations are one of the unusual manifestations of dengue infection. OBJECTIVES: We conducted this study in order to study the pattern of serum aminotransferases and sequential changes before and after shock in Thai children with dengue infection. PATIENTS AND METHODS: Children who were clinically and serologically diagnosed as dengue infection and were admitted to King Chulalongkorn Memorial Hospital during a peroid of one year were enrolled. They were clinically classified into a non-shock group and a shock group. The majority of serum aminotransferases including aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were obtained within a week after the onset of fever and until 3 days after shock in the shock group. Student t-test and median in boxplot form were used for statistical analysis. RESULTS: We enrolled 127 children with a mean age of 7.6 ± 3.6 years. The incidence of abnormal AST and ALT levels was 97.4% and 50.0% in the shock group, and 91.8% and 44.9% in the non-shock group respectively. 29% and 15.4% of the patients in shock group and only 10.2% and 4.1% in non-shock group had the respective AST and ALT levels > 200 U/L. Serum aminotransferase levels were significantly higher in the shock group when compared to the non-shock group. AST tended to increase starting from one day before shock and continued to increase within a few days whereas ALT was less likely to be affected. CONCLUSIONS: Elevated serum aminotransferases are a common finding in children with dengue infection and the levels of AST are higher than those of ALT. Patients with shock have significantly higher aminotransferase levels that increase up to 3 days after shock.

DENGUE: GLOBAL THREAT.

Dengue is a mosquito-borne viral disease, which is currently an expanding global problem. Four closely related dengue serotypes cause the disease, which ranges from asymptomatic infection to undifferentiated fever, dengue fever (DF), and dengue hemorrhagic fever (DHF). DHF is characterized by fever, bleeding diathesis, and a tendency to develop a potentially fatal shock syndrome. Dengue infection with organ impairment mainly involves the central nervous system and the liver. Consistent hematological findings include vasculopathy, coagulopathy, and thrombocytopenia. Laboratory diagnosis includes virus isolation, serology, and detection of dengue ribonucleic acid. Successful treatment, which is mainly supportive, depends on early recognition of the disease and careful monitoring for shock. A severity-based revised dengue classification for medical interventions has been developed and validated in many countries. There is no specific dengue treatment, and prevention is currently limited to vector control measures. The world's first, large-scale dengue vaccine efficacy study demonstrated its efficacy and a reduction of dengue disease severity with a good safety profile in a study of more than 30,000 volunteers from Asia and Latin America.

HEMOSTATIC STUDIES IN DENGUE PATIENTS.

The pathogenesis of hematologic changes in dengue patients is not clearly understood. Consistent hematological findings include vasculopathy, thrombocytopenia, and coagulopathy. There are evidences suggesting that dengue virus causes pathophysiological changes that involve all of the consistent hematologic findings resulting in vasculopathy, reduction in platelet number as well as platelet dysfunction, and reduction of several coagulation factors. Laboratory evidences of disseminated intravascular coagulation (DIC) are also demonstrated in all degrees of severity in dengue patients. Only in severe dengue cases is profound DIC aggravated, leading to uncontrolled bleeding and death. A study to determine the extent of the activation of endothelial cells and the hemostatic system in correlation with clinical severity and also to detect the best prognostic factor for severe dengue showed plasma von Willebrand factor antigen (VWF:Ag) to be the best indicator of progression to severe dengue.

DENGUE WITH CENTRAL NERVOUS SYSTEM INVOLVEMENT.

Dengue has spread to new geographic areas affecting both children and adults, and it has become a global threat. Dengue with central nervous system involvement includes febrile seizures, encephalopathy, encephalitis, aseptic meningitis, intracranial hemorrhages, intracranial thrombosis, subdural effusions, mononeuropathies, polyneuropathies, Guillain-Barré syndrome, and transverse myelitis. These manifestations may be associated with co-infections, co-morbidities, or complications of prolonged shock. It is important to consider dengue as a cause for the above neurological presentations, particularly in endemic territories for dengue disease.

DENGUE VACCINES.

The uniqueness of the dengue viruses (DENVs) and the spectrum of disease resulting from infection have made dengue vaccine development difficult. Several vaccine candidates are currently being evaluated in clinical studies. The candidate currently at the most advanced clinical development stage, a live-attenuated tetravalent vaccine based on the chimeric yellow fever-dengue virus (CYD-TDV), has progressed to Phase 3 efficacy studies. Several other live-attenuated vaccines, as well as subunit, DNA, and purified inactivated vaccine candidates are at earlier stages of clinical development. Additional technological approaches, such as virus-vectored and Virus-Like Particles (VLP)-based vaccines are under evaluation in preclinical studies.

Dengue: a global threat.

Dengue, a mosquito-borne viral disease, is currently an expanding global problem. The disease is caused by four closely related dengue serotypes; it ranges from asymptomatic infection to undifferentiated fever, dengue fever (DF) and dengue hemorrhagic fever (DHF). DHF is characterized by fever, bleeding diathesis and a tendency to develop apotentially fatal shock syndrome. Dengue infection with organ impairment mainly involves the central nervous system and liver. Consistent hematological findings include vasculopathy, coagulopathy and thrombocytopenia. Laboratory diagnoses include virus isolation, serology, and detection ofdengue ribonucleic acid. Successful treatment, which is mainly supportive, depends on early recognition of the disease and careful monitoring for shock. A severity-based revised dengue classification for medical interventions has been developed and validated in many countries. So far however, there has not been any specific dengue treatment; prevention is currently limited to vector control measures. The world's first, large-scale dengue vaccine, efficacy study demonstrated its efficacy and a reduction of dengue's severity in a study of more than 10,000 volunteers in Asia. Initial safety data are consistent with a good safety profile.

Latest developments and future directions in dengue vaccines.

Dengue is a mosquito-borne disease which is currently an expanding global health problem. The disease is caused by four closely related viruses, the dengue virus. There are no specific dengue therapeutics and prevention is currently limited to vector control measures. Development of an effective tetravalent dengue vaccine would therefore represent a major advance in the control of the disease and is considered a high public health priority. While a licensed dengue vaccine is not yet available, the scope and intensity of dengue vaccine development has increased dramatically in the last decade. The uniqueness of the dengue viruses and the spectrum of disease resulting from infection have made dengue vaccine development difficult. Several vaccine candidates are currently being evaluated in clinical studies. The candidate currently at the most advanced clinical development stage, a live-attenuated tetravalent vaccine based on chimeric yellow fever dengue virus, has progressed to phase III efficacy studies. Several other live-attenuated vaccines, as well as subunit, DNA and purified inactivated vaccine candidates, are at earlier stages of clinical development. Additional technological approaches, such as virus-vectored and virus-like particle-based vaccines, are under evaluation in preclinical studies.

Dengue: A growing global health threat

@#Dengue infection, one of the most devastating mosquito-borne viral diseases in humans, is now a significant problem in many countries. The disease, caused by the four dengue virus serotypes, ranges from asymptomatic infection to undifferentiated fever, dengue fever (DF), and severe dengue hemorrhagic fever (DHF) with or without shock. DHF is characterized by fever, bleeding diathesis and a tendency to develop a potentially fatal shock syndrome. Dengue infection with organ impairment mainly involves central nervous system and liver. Consistent hematological Findings include vasculopathy, coagulopathy, and thrombocytopenia. Laboratory diagnosis includes virus isolation, serology, and detection of dengue ribonucleic acid. Successful treatment, which is mainly supportive, depends on early recognition of the disease and careful monitoring for shock. A severity-based revised dengue classification for medical interventions has been developed and validated in many countries. Prevent depends primarily on control of the mosquito vector. The feasibility of a dengue vaccine is high.

Dengue infection: a growing global health threat.

Dengue infection, one of the most devastating mosquito-borne viral diseases in humans, is now a significant problem in several tropical countries. The disease, caused by the four dengue virus serotypes, ranges from asymptomatic infection to undifferentiated fever, dengue fever (DF), and severe dengue hemorrhagic fever (DHF) with or without shock. DHF is characterized by fever, bleeding diathesis and a tendency to develop a potentially fatal shock syndrome. Consistent hematological findings include vasculopathy, coagulopathy, and thrombocytopenia. There are increasing reports of dengue infection with unusual manifestations that mainly involve cerebral and hepatic symptoms. Laboratory diagnosis includes virus isolation, serology, and detection of dengue ribonucleic acid. Successful treatment, which is mainly supportive, depends on early recognition of the disease and careful monitoring for shock. Prevention depends primarily on control of the mosquito vector. Further study of the pathogenesis of DHF is required for the development of a safe and effective dengue vaccine.

Hepatosplanchnic circulatory dysfunction in acute hepatic infection: the case of dengue hemorrhagic fever.

The mechanism of shock in patients with dengue hemorrhagic fever (DHF) has not yet been fully understood. In this study, we investigated the possibility of splanchnic venous pooling as a contributor for circulatory dysfunction in these patients. Ultrasonographic studies of portal vein and inferior vena cava were done in 45 patients with serologically or PCR-confirmed diagnosis of dengue virus infection. The size of portal vein and inferior vena cava, mean blood flow velocity in the right portal vein, and modified portal vein congestion index were compared between patients with dengue fever (DF, n = 20), DHF without shock (n = 14), and dengue shock syndrome (DSS, n = 11) during the toxic stage, convalescent stage, and at follow-up. The portal vein was significantly more dilated in patients with shock (DSS) than DHF without shock and than DF during the toxic and convalescent stages (P < 0.05), but not at follow-up. The change in the size of inferior vena cava followed the opposite trend (not statistically significant). Portal vein blood flow velocity was lower and congestion index was higher in shock cases (DSS) than DHF without shock and than DF at toxic and convalescent stages (P < 0.01). The differences disappeared at follow-up. Hepatosplanchnic venous pooling and/or dysfunction occur and correlate with the severity of circulatory derangement and shock in patients with DHF. The cause(s) and significance of hepatosplanchnic circulatory dysfunction in DHF and possibly other viral hepatic diseases deserve further study.

Concomitant dengue infection and Kawasaki disease in an infant: a case report and literature review.

A previously healthy 11-month-old girl presented with fever and rash for 6 days. Physical examination revealed an irritable infant with a high fever, injected conjunctivae, red cracked lips, posterior auricular lymphadenopathy, hepatomegaly, generalized erythematous maculopapular rash and petechial hemorrhage on trunk, face and extremities. Complete blood count showed atypical lymphocytosis and thrombocytopenia. Dengue infection was initially diagnosed. The persistent fever and clinical manifestations of Kawasaki disease (KD) were observed on day 8 with high erythrocyte sedimentation rate (56 mm/hr). Treatment of KD included intravenous immunoglobulin on day 9 of the illness. Desquamation of the fingers was found on day 15 of the illness. Ectasia of left coronary artery with small aneurysmal dilatation was detected by echocardiography on day 15 of the illness. Hemagglutination-inhibition test and enzyme-linked immunosorbent assay for dengue virus eventually showed a four-fold rising. According to the literature review, this is the second reported case of dengue infection concomitant with KD. The natural course of each disease may be modified and causes some difficulties in diagnosis and management.

Infective endocarditis in pediatric patients: an eighteen-year experience from King Chulalongkorn Memorial Hospital.

OBJECTIVES: To review the clinical features and outcome of the pediatric patients diagnosed with infective endocarditis (IE) at King Chulalongkorn Memorial Hospital over an 18-year period. MATERIAL AND METHOD: From January 1987 to December 2004, 57 pediatric patients; 28 females and 29 males, age ranged from 2 months to 15 years, mean of 8.64 +/- 3.82 years, classified as "definite" IE according to the Duke criteria were reviewed. RESULTS: Of the 57 patients, 42 patients (74%) had underlying congenital heart diseases, 7 patients (12%) had underlying rheumatic heart disease, 8 patients (14%) had previously normal heart. Nine patients had history of previously palliative or corrective surgery. Blood cultures were positive in 26 patients (46%). Streptococci and staphylococci were the most commonly isolated organisms. Two-dimensional echocardiography demonstrated vegetations in 56 patients (98%). The location of the vegetations was in the right heart in 30 patients (54%) and in the left heart in 26 patients (46%). Complications occurred in 28 patients (49%). Common complications included congestive heart failure, cerebral emboli, septic shock, and mycotic aneurysm. The overall mortality was 11% (6 patients). By statistical analysis, vegetations in the left heart had a higher incidence of complication than that in the right heart. The vegetation size of > or =10 mm had a significant higher incidence of embolic events. CONCLUSION: The clinical features and outcomes of the present study have a similar pattern as the earlier studies. The rates of complications and mortality are still high.

A cost-benefit analysis of intravenous immunoglobulin treatment in children with Kawasaki disease.

To determine the long-term cost-benefit of intravenous immunoglobulin (IVIG) treatment in Children with Kawasaki Disease (KD), a model was made to compare the total cost for management of these children with and without the use of IVIG. Long-term (10-21 years) follow-up of 594 KD patients treated in the pre-IVIG era reported by Kato, et al. was used to calculate cost using previous cost studies from Chulalongkorn Hospital. Reduction of CAA from 25 per cent to 4 per cent with IVIG treatment was assumed based on previous published data. Total cost was slightly lower for the non-IVIG treatment group compared to the IVIG treatment group (33,451,129 baht vs 35,001,195 baht) for the duration of follow-up in Kato's model. Cost per effectiveness analysis showed more effectiveness in the IVIG treatment group (359,576 baht vs 383,614 baht). Net cost analysis similarly demonstrated lower costs in the IVIG treatment group (25,365,215 baht vs 33,451,129 baht). Incremental cost-effectiveness analysis demonstrated supplementary costs of 13,663 baht for one case in the reduction of coronary involvement and 387,517 baht for one life saved in the IVIG-treated group. Estimation of total costs for follow-up and treatment for healthy life (until 60 years old) was more expensive in the non-IVIG treatment than the IVIG treated group (75,482,803 baht vs 29,883,833 baht). The authors conclude that treatment of all KD cases in Thailand with IVIG is likely to result in lower cost and better outcome when compared to no treatment with the IVIG policy.

Selection of coil for transcatheter closure of small patent ductus arteriosus.

The authors reported the results in transcatheter coil occlusion of patent ductus arteriosus (PDA) less than 4 mm, based on a policy in selection of the appropriate type and number of coils for size of PDA. The authors used one 0.035 inch detachable coil, 5 mm in diameter, in PDA less than or equal to 2 mm, and two 0.035 inch detachable coils or one controlled release 0.052 inch Gianturco coil in PDA larger than 2 mm. The present study included 32 pediatric patients. There were 31 cases of successful coil implantation and 1 case failed. Of the 31 successful cases, PDA size varied from 1.4 to 4.0 mm (mean of 2.7 +/- 0.9 mm). Ten patients had a PDA size of less than or equal to 2 mm (group A), while the other 21 patients had a PDA size of larger than 2 mm (group B). In group A, 9 cases had single-detachable-coil occlusion and one case had double-detachable-coil occlusion. In group B, double-detachable-coil occlusion was performed in 17 cases and controlled release 0.052 inch coil in 4 cases. There were no cases of coil migration or other serious complications. The immediate complete occlusion rate was 58 per cent (18 of 31 cases), which rose to 97 per cent (30 of 31 cases) at the mean follow-up of 2.6 +/- 2.5 months (range from 1 day to 9 months). Transcatheter coil occlusion is an alternative to surgical closure of small PDA (less than 4 mm). Selection of type and number of coils appropriate to the size of PDA will allow safe and excellent results.

Dengue infection: a global concern.

Dengue infection, one of the most important mosquito-borne viral diseases of humans, is now a significant problem in several tropical countries. The disease, caused by the four dengue virus serotypes, ranges from asymptomatic infection, undifferentiated fever, dengue fever (DF) to severe dengue hemorrhagic fever (DHF) with or without shock. DHF is characterized by fever, bleeding diathesis and a tendency to develop a potentially fatal shock syndrome. Hematological findings include vasculopathy, coagulopathy and thrombocytopenia as the most constant findings. During the last twenty-five years, there have been increasing reports of dengue infection with unusual manifestations, mainly with cerebral and hepatic symptoms. Laboratory diagnosis includes virus isolation, serology and detection of dengue ribonucleic acid. Successful treatment, which is mainly supportive, depends on early recognition of the disease and careful monitoring for shock. Prevention depends on control of the mosquito vector. More efforts must be made to understand the pathogenesis of DHF in order to develop a safe and effective dengue vaccine.

Endocarditis and pericarditis caused by Salmonella paratyphi A: two case reports and review of the literature.

We report on two children with paratyphoid fever and rare cardiac complications (endocarditis and pericarditis) during an outbreak of Salmonella paratyphi A infection in Bangkok, Thailand, in 1996. Both of the patients had underlying congenital heart disease. Two cases in the literatures of endocarditis and five cases of pericarditis caused by Salmonella paratyphi were reviewed. These rare cardiac complications should be considered among persons who reside in an endemic area of enteric fever or during disease outbreaks, especially in children with underlying heart diseases.