Is there a need for a travel vaccination against tick-borne encephalitis?

Tick - borne encephalitis is a vector-borne disease primarily transmitted to humans by the bite of infected ticks. Clinical presentations range from mild meningitis to severe encephalitis with or without myelitis and may result in long-term neurological equelae or death. The disease can successfully be prevented through active immunization. BE is endemic in regions of at least 26 European countries. The risk of contracting TBE in the most affected countries has increased in the past 20 to 30 years, between 1974 and 2003, the number of reported clinical TBE cases increased by an appalling 400%, the only exception having been Austria. Because of increasing international travel streams of tourists from non-endemic countries to TBE risk areas, the infection is now becoming a more important issue of travel medicine.The risk depends on both the travelling season and the degree of unprotected outdoor exposure to forest areas (e.g. bicycling, camping, hiking, etc.). Tourists are by no means aware of the actual risk potential, especially when travelling to a knowingly 'safe' Europe. Vaccination against tick-borne encephalitis may be required for some tourists, depending on travel destination and behaviour. Implementing general guidelines for the use of TBE travel vaccination should be put on the agenda for travel medicine.     

Tegaserod inhibits noxious rectal distention induced responses and limbic system c-Fos expression in rats with visceral hypersensitivity

AIM:To examine the effects of tegaserod,a serotonin(5-HT)4 receptor partial agonist,on abdominal withdrawalreflex(AWR)to rectal distention(RD)and c-Fos expressionin limbic system.METHODS:Neonatal Sprague-Dawley rats randomlyreceived colonic irritation by acetic acid from postnatal day8 to d 21 as a visceral hypersensitive model(group H)or byintrarectal saline as a control group(group C).When theybecame adults,rectal distention(RD)was performed by aballoon(6F;Fogarty arterial embolectomy catheter;length,20 mm;diameter,2 mm)which was rapidly inflated withincreasing volumes of saline(0.4,0.8 and 1.2 mL)for 20 sat five-minute intervals.Five subgroups of group H(H-saline,H-vehicle,H-Teg0.1,H-Teg0.3 and H-Teg1.0) were injectedrandomly with saline,vehicle(1-methyl-2-thpyrrolidone)ortegaserod at doses of 0.1,0.3 and 1.0 mg/kg ip,respectively.Two subgroups of group C(C-Saline and C-Teg1.0)wereinjected with saline or tegaserod(1.0 mg/kg)ip.RD wasperformed 10 rain after injection,AWR was recorded andc-Fos expression in limbic system was analyzed quantitativelyby immunohistochemistry.RESULTS:Compared to saline,tegaserod significantlyinhibited AWR in group H(0.4 mL:from 2.0 to 0.5;0.8 mL:from 3.5 to 1.5;1.2 mL:from 4.0 to 3.0,P<0.01),but hadno significant effect on group C.Tegasered dose-dependentlyattenuated the number of c-Fos positive neurons in limbicstructures,anterior cingulate cortex(ACC)showed thegreatest attenuation.In group H,tegaserod(1.0 mg/kg)resulted in a significant overall decrease to 57% of H-saline(283±41 vs 162±16,P<0.01),in ACC to 42% of H-saline(72±10 vs 31±8,P<0.01).In group C,tegaserod(1.0 mg/kg)resulted in an overall decrease to 77% of C-saline(214±13vs 164±22,P<0.01),in ACC to 65% of C-saline(48±8 vs31±7,P<0.01).CONCLUSION:Tegaserod inhibits the response to rectaldistention in rats with visceral hypersensitivity and dose-dependently attenuates c-Fos expression in limbic system,especially in anterior cingulate cortex.     

Current characteristics of natural nidality of tick-borne encephalitis: new or well forgotten?

A number specialists' opinion as to which the rise in the incidence of tick-borne encephalitis at the turn of the centuries is due to the new features of the epidemiology of this infection and to global climatic changes is analyzed. There are no objective evidence suggesting the ongoing expansion of a natural habitat of the major vectors--taiga (Ixodes persulcatus) and wood (I. ricinis) ticks and the noticeable increase in their size and virus infection rates. The notion of the recent penetration of ticks into the metropolises where natural focuses have emerged and human beings are infected is inconsistent with the multidescribed facts. There is no significant evidence for the expansion of a nosoarea of tickborne encephalitis. The impact of reformed anthropurgic foci and that of the proportion of town-dwellers in the general structure of morbidity on the epidemic situation have been evaluated. The intensity of an epidemic manifestation of natural foci is always determined by two most important parameters: 1) the loimopotential of foci and 2) the intensity of the population's contact with them. The nature of an interaction between these factors, which has caused a rapid surge of morbidity rates and their subsequent long-time reduction, is considered.     

Increasing trend of Japanese encephalitis cases in West Bengal,India – a threat to paediatric population

ObjectiveTo detect the Japanese encephalitis virus (JEV) as the etiologic agent from the acute encephalitis syndrome (AES) cases mainly amongst the children and young adults from vaccinated and non-vaccinated districts of West Bengal.MethodsFor the detection of JEV, a total of 828 sera were referred from vaccinated and non vaccinated districts of West Bengal during 2005-2011. Japanese encephalitis (JE) positive cases were confirmed by ELISA and RT-PCR method.ResultsOut of 828 cases, 245 samples were positive by ELISA method and 46 samples were positive by RT-PCR method. Out of 291 total positive cases, 162 (55.6%) were below 20 years of age. Initially in 2005, JE cases were highest amongst the children and young adults (0-20 years). After vaccination, although the JE cases declined gradually in the vaccinated districts, but again from 2010, JE cases from the said age group showed an increasing trend from those districts. JE cases were also reported from other endemic zones of this state, which were still non-vaccinated.ConclusionsIn West Bengal, JE cases are still predominated among children and young adults till the year 2011. Mass scale vaccination programme and investigation on the circulating strains are essentially required to find out the reasons of increasing tendency of JE cases in this state.     

Red fox and tick-borne encephalitis (TBE) in humans: can predators influence public health?

Analysing datasets from hunting statistics and human cases of tick-borne encephalitis (TBE), we found a positive correlation between the number of human TBE cases and the number of red fox (Vulpes vulpes). Time lags were also present, indicating that high numbers of red fox in 1 y translated into high numbers of human TBE cases the following y. Results for smaller predators were mixed and inconsistent. Hares and grouse showed negative correlations with human TBE cases, suggesting that they might function as dilution hosts. Combining our findings with food web dynamics, we hypothesize a diversity of possible interactions between predators and human disease - some predators suppressing a given disease, others enhancing its spread, and still others having no effect at all. Larger-sized predators that suppress red fox numbers and activity (i.e. wolf, Canis lupus; European lynx, Lynx lynx) were once abundant in our study area but have been reduced or extirpated from most parts of it by humans. We ask what would happen to red foxes and TBE rates in humans if these larger predators were restored to their former abundances.     

Secondary neuropsychiatric manifestations caused by Epstein–Barr virus encephalitis in a new onset systemic lupus erythematosus patient

Abnormal manifestations of central nervous system in system lupus erythematosus (SLE) patients are mainly caused by primary neuropsychiatric SLE (NP-SLE). We reported a new onset SLE patient who had secondary neuropsychiatric manifestations caused by Epstein–Barr virus (EBV) encephalitis. Although EBV has an uncertain association with SLE, Epstein–Barr virus encephalitis occurred in active SLE patients was not reported previously. Our report may be the first case about EBV encephalitis occurred in active SLE.     

Seroepidemiology of neutralizing antibodies to Japanese encephalitis virus in Singapore: continued transmission despite abolishment of pig farming?

Japanese encephalitis virus (JEV) transmission in Singapore appeared to have ceased after pig farming in Singapore was phased out from the early 1980s. However, the recent detection of neutralizing antibodies to JEV in a population of wild boars in an offshore island, as well as the notification of two human cases of JE in Singapore in 2001, prompted us to reconsider the presence and hence the public health threat of JEV in Singapore. We report here a serological study of animals, birds and humans for neutralizing antibodies to JEV. The results indicate that JEV may still be actively transmitted in the peripheral part of the Singapore island and that regular serological surveys of farm animals and birds, such as chickens, may be useful to further elucidate the activity of JEV in Singapore.     

Toxoplasma encephalitis in AIDS patients in São Paulo during 1988 and 1991. A comparative retrospective analysis

We conducted a retrospective analysis of Toxoplasma encephalitis patients from Instituto de Infectologia Emílio Ribas, the main AIDS hospital of S?o Paulo, Brazil, during two different stages of the HIV epidemics, in 1988 (38 patients) and 1991 (33 patients). There were AIDS-related demographic differences, but the clinical presentation and diagnostic efficiency were similar, usually based on tomography and clinical response to therapy, with a clear distinction from other CNS infections, based on clinical and laboratory findings. Specific serologic studies were performed less often in 1991, with a high frequency of therapy change. The direct acute death rate from Toxoplasma encephalitis was high during both periods, i.e. 8/38 in 1988 and 10/33 in 1991. The direct acute death rate for the patients from the two periods as a whole was 25.4% (18/71), related to the time of HIV infection, absence of fever and presence of meningeal irritation at presentation, blood leukocytes higher than 10,000/mm3 and blood lymphocytes lower than 350/mm3. Toxoplasma encephalitis is a preventable disease when adequate prophylactic therapy is used and is relatively easy to treat in diagnosed HIV patients. Unfortunately, this severe and deadly disorder is the HIV diagnostic disease in several patients, and our data support the need for careful management of these patients, especially in those countries with a high toxoplasmosis prevalence where AIDS is concurrent with economic and public health problems.