Neurological complications in Chikungunya fever

OBJECTIVE

The present prospective study was undertaken to study the clinical manifestations and mainly neurological complication of an acute febrile illness termed chikungunya which has recently attacked india after 43 years.

METHOD

This prospective study has been conducted in hospitalised patients admitted in government and private hospitals of Kota city from August 2006 to October 2006. Patients showing neurological involvement with typical clinical picture of chikungunya infection were studied in detail and followed up for improvement and any permanent damage or death.

RESULTS

Apart from typical clinical triad of high grade fever, arthralgia and rash of chikungunya infection we have observed a spectrum of neurological abnormalities in terms of altered mental functions, seizures, focal neurological deficit with abnormal CT scan of head and altered CSF biochemistry. Permanent neurological sequelae and even death has occurred.

CONCLUSION

Typical clinical history of chikungunya infection, neurological complications with associated CSF abnormalities, supportive laboratory evidences, positive chikungunya IgM card test, exclusion of other causes and known predilection of arboviruses for CNS infection allows us to conclude the diagnosis of study cases as Chikungunya Encephalitis.

Porcine reproductive and respiratory syndrome: NEB-1 PRRSV infection did not potentiate bacterial pathogens

A 2-phase study was conducted to evaluate the ability of the NEB-1 strain of porcine reproductive and respiratory syndrome virus (PRRSV) to potentiate common bacterial pathogens of swine. In phase I, 25 of 50 4-5-week-old specific-pathogen-free (SPF) pigs were exposed to NEB-1 PRRSV (day 0). Seven days after virus inoculation, 8 groups received 1 of 4 bacterial pathogens: Haemophilus parasuis, Streptococcus suis, Salmonella cholerasuis, and Pasteurella multocida. The ability of NEB-1 PRRSV to produce clinical disease, viremia, neutralizing antibody, gross and microscopic lesions and to potentiate bacterial pathogens was assessed. Response to NEB-1 PRRSV was similar among inoculated pigs; prolonged hyperthermia, lethargy, mild to moderate dyspnea, and cutaneous erythema were consistent clinical signs. No clinical differences were observed in groups after bacterial challenge. Virus was isolated from serum at weekly intervals through the end of the study, and all PRRSV-inoculated pigs had seroconverted by study termination. Two of 5 pigs died in non-PRRSV-inoculated groups challenged with H. parasuis and Streptococcus suis. Mortality in PRRSV-infected pigs was limited to 1 of 5 pigs from the Salmonella cholerasuis-challenged group. Gross lesions were seen in pigs dying after inoculation in H. parasuis- and Streptococcus suis-inoculated groups, in Salmonella cholerasuis- and P. multocida-challenged pigs, and in 1 non-PRRSV-inoculated control pig. Microscopic lesions consisted of mild to moderate proliferative interstitial pneumonia, nonsuppurative myocarditis, lymphoid hyperplasia, and nonsuppurative encephalitis in PRRSV-inoculated pigs. Findings in phase I indicated that NEB-1 PRRSV does not potentiate bacterial disease while inducing consistent clinical signs, viremia, seroconversion, and microscopic lesions.(ABSTRACT TRUNCATED AT 250 WORDS)

Viral infection including HIV and AIDS

Viruses have long been considered candidates for infectious etiologic agents or cofactors in the development of rheumatic diseases. The current epidemic of HIV infection and the recognition of "emerging viruses" has focused interest on the possible role of viruses in pathogenesis of diseases without defined etiology. Over the past year, the role of parvovirus B19 in chronic arthropathy was further defined. Additional data added to our understanding of the mechanisms by which rubella virus may cause chronic arthritis. We were reminded of the potential the togaviruses have to cause epidemics of febrile arthritis. The developing story of hepatitis C virus in essential mixed cryoglobulinemia encourages us to explore strategies for specific antiviral therapies. The members of the herpesvirus family came under scrutiny for their role in Sjögren's syndrome. The retroviruses continue to attract attention because of rheumatic disease syndromes in AIDS patients and the suggestion that still undefined retroviruses may play an etiologic role in rheumatoid arthritis. This review highlights efforts made in the past year to elucidate the role of viral infection in rheumatologic disease.

High mortality of domestic turkeys associated with Highlands J virus and eastern equine encephalitis virus infections

High mortality occurred in two flocks of commercial turkey hens placed in southern North Carolina in fall 1991. Daily mortality peaked at 3.19% in Flock 1 and 3.79% in Flock 2. Clinical signs included restlessness, somnolence, vocalization, and acute death. Gross lesions included atrophy of the bursa of Fabricius, thymus, and spleen, and watery intestinal contents. Microscopic changes included moderate to marked lymphocyte necrosis and depletion in the bursa, thymus, and spleen, widely scattered necrosis of pancreatic acinar cells, and mild villous atrophy and fusion in the jejunum and ileum with cuboidal to low columnar epithelial cells covering the villous tips. In Flock 1, at 27 days of age, reovirus and picornavirus particles were detected in the feces. One week later, togavirus-like particles were observed in fecal contents, and two of seven serum samples showed seroconversion to Highlands J virus. Eleven days later, five of six serum samples were positive for antibodies against Highlands J virus, with a fourfold increase in the geometric mean titer. In Flock 2, seroconversion to eastern equine encephalitis virus was observed in four of 10 serum samples 11 days after the onset of clinical signs. Based on the above observations, it is suspected that these alphaviruses were the cause of the clinical syndrome.

Virological and immunological studies of Wesselsbron virus in experimentally infected red Sokoto (Maradi) goats

Red Sokoto goats aged four to five months were experimentally infected with the Nigerian strain of Wesselsbron virus. Viraemia commenced 24-72 hours after infection and lasted for 3-4 days. A febrile reaction which was mostly biphasic coincided with viraemia. A 50% mortality rate was observed among infected animals. The virus was re-isolated in mice from almost every tissue (liver, spleen, lungs, brain, kidney, adrenal, lymph node and heart) obtained from dead goats. Complement fixing antigens were detected in the tissues of dead goats, the titre of which correlated positively with the infectivity titre. All infected animals developed complement-fixing and haemagglutination inhibiting antibodies to Wesselsbron virus. However, neutralizing antibody was detected only in goats that survived the infection.

Viruses as teratogens

The ability of certain viruses to affect prenatal development in domestic animals is well documented. However, differentiating a viral-induced malformation from those caused by genetic or other environmental causes is a diagnostic dilemma. Understanding how viruses interact with their embryo-fetal hosts and the potential consequences on prenatal development requires refining and dispelling some old concepts and injecting new insights into this diagnostic challenge. This article discusses several viral teratogens affecting domestic animals: Akabane, bluetongue, Cache Valley, Japanese B encephalitis, bovine viral diarrhea, Border disease, Chuzan, epizootic hemorrhagic disease, hog cholera, Rift Valley fever, and Wesselsbron disease viruses.

Serological and antigenical findings indicating pestivirus in man

An epidemiological survey for pestivirus was undertaken in Zambia and Europe, in view of the recent serological findings obtained by previous studies in Europe with humans. Collected sera were tested for anti-bovine viral diarrhea virus (BVDV) specific antibodies by IIF and Western Blotting. Of those individuals tested (n = 1272), 15.3% showed a seropositive reaction to the BVDV. Anti-BVDV antibody prevalence in immuno-depressed patients (e.g. HIV positive) was investigated. A higher prevalence was revealed in HIV patients suffering from chronic diarrhoea and in those having developed AIDS Related Complex (ARC). Our of 212 persons tested for pestivirus isolation, a non cytopathic virus strain was detected in 2 buffy coat samples using IIF with a specific anti-BVDV serum. The isolation could be repeated three times during 31 days in one person. The virus was identified as a pestivirus with radioimmuno-precipitation assays and IIF-flow cytometry. A doublet of 120 kD was identified only in cell lysates, indicating a non-structural protein. In order to rule out cross reactivity 30 sera from Hepatitis C seropositive patients were tested against the isolate by IIF-flow cytometry. No antigen-specific binding could be observed. These findings indicated the occurrence of a pestivirus in man and might suggest a relationship with a pestivirus of animal origin.

Murray Valley encephalitis acquired in Western Australia

OBJECTIVE

To report a recent fatal case of encephalitis associated with evidence of Murray Valley encephalitis virus infection, only the second fatality from this infection in Western Australia.

CLINICAL FEATURES

An 18-month-old Aboriginal boy was admitted to hospital in northwest Western Australia with proven Haemophilus influenzae type b meningitis.

INTERVENTION AND OUTCOME

After an initial good response to antibiotics (amoxycillin and cefotaxime) he relapsed and died with evidence of encephalitis. Analysis of serum showed a high titre of antibody to Murray Valley encephalitis (MVE) virus with the presence of specific IgM. No evidence was found for other infective agents.

CONCLUSION

It is likely that this child died from MVE which followed his bacterial meningitis. Of the strains of mosquitoes trapped in the area of suspected infection 77.8% were Culex annulirostris, the major vector species for MVE. No MVE virus was isolated from these mosquitoes, but serum from one of the sentinel chickens contained MVE virus antibodies, indicating the presence of the virus in that region.

Abnormalities of responses to autonomic stimulation in the mouse urinary bladder associated with Semliki Forest virus-induced demyelination

The responses to autonomic stimulation of the urinary bladder were studied in mice infected with Semliki Forest Virus, which has been proposed as an animal model for multiple sclerosis. Mice infected with Semliki Forest Virus showed a decreased body weight when compared with control animals, although their bladders were proportionately heavier. The pharmacological results indicated a selective change in purinergic transmission in the bladders of mice infected with Semliki Forest Virus, while cholinergic transmission remained unchanged. This was demonstrated by a significant increase in the contractile response to beta,gamma-methylene ATP accompanied by an increase in the proportion of the nerve-mediated response blocked by alpha,beta-methylene ATP. In contrast, the contractile response to acetylcholine and the atropine-sensitive component of the neurogenic response were not significantly different between the two groups of animals. Active length-tension curves were also unchanged in the mice infected with Semliki Forest Virus when compared with controls. The results are discussed in relation to those obtained from models of urinary bladder dysfunction associated with hypertrophy; whether the alteration of atropine-resistant (purinergic) function reported here is a general secondary feature of this type of bladder dysfunction or a change specific to the Semliki Forest Virus model of multiple sclerosis is not resolved. This study provides evidence that peripheral changes as well as central nervous system demyelination occur in the Semliki Forest Virus-infected mouse.

Infantile gastroenteritis associated with excretion of pestivirus antigens

Faeces from children under 2 years old who had gastroenteritis that could not be attributed to recognised enteric pathogens were examined with a monoclonal-antibody-based immunoassay for Pestivirus antigens. Such antigens were detected in 30 of 128 episodes of gastroenteritis. Children without diarrhoeal disease and children infected with rotaviruses had little evidence of Pestivirus infection (faeces positive in 1 of 28 and 1 of 31, respectively). The diarrhoeal disease in children excreting Pestivirus antigens resembled that in other children except that it was more commonly associated with signs and symptoms of respiratory inflammation.

Aetiology of Kawasaki disease

Thirteen serum samples from nine children with Kawasaki disease and 23 control samples gave negative results on screening for antibodies to hog cholera virus, border disease of sheep, bovine diarrhoea virus, and equine arteritis virus. The sera from two children with Kawasaki disease were cytotoxic; a possible link with cytotoxin from Propionibacterium acnes is considered.

Differentiation of hog cholera and bovine virus diarrhoea viruses in pigs using monoclonal antibodies

Monoclonal antibodies against hog cholera and bovine viral diarrhoea viruses were assayed on organ tissue sections of experimentally infected animals. The animals had been infected simultaneously with both viruses. The antibodies were tested using an indirect immunofluorescence test and an indirect enzyme immunoassay with a biotin/streptavidin/peroxidase detection system. A polyclonal hyperimmune serum was used as a control in direct immunofluorescence tests. Both techniques based on monoclonal antibodies were more sensitive and more specific than the conventional test, the enzyme immunoassay being more sensitive than the immunofluorescence test. Small amounts of BVD viral antigen were demonstrable with monoclonal antibodies in most organ tissues.

Enhancement of demyelination in the central nervous system of Semliki Forest virus infected mice after pretreatment with muramyl dipeptide

Semliki Forest virus infections in mice produce an encephalitis with demyelination. If before giving the virus the mice are treated with muramyl dipeptide in Freund's incomplete adjuvant, there is a significant increase in demyelination. If ovalbumin is added to the above and then followed after an interval by a second dose of ovalbumin and finally by the virus, the demyelination is further, but only marginally increased. The addition of ovalbumin without muramyl dipeptide in the schedule appears to increase the number of infiltrating cells and to a lesser extent the perivascular cuffing, but does not increase the demyelination as compared to that obtained when Semliki Forest virus is given on its own.

A study of viral and rickettsial exposure and causes of fever in Juba, southern Sudan

Patients presenting at the Juba Teaching Hospital, either with fever of undetermined origin or with a clinical cause of fever, gave evidence of exposure to a wide range of viral and rickettsial agents. Serological tests showed high antibody levels to flaviviruses (56.9%) and alphaviruses (29.2%), with lesser levels of bunyamweraviruses (3.8%), Rift Valley fever (2.3%), and sandfly fever (0.75%). Flavivirus exposure was significantly associated with clinical evidence of liver disease; repeated exposure to flaviviruses was particularly prevalent in those with poor sanitation and who had received previous injections. A significant focus of Ebola and Marburg exposure in Juba has been identified. Clinical evidence of liver disease was evident in 37% of patients studied, and 24.6% were HBsAg positive. The first 2 HIV-positive individuals from the southern Sudan are reported, including one with clinical AIDS. A high prevalence of positive antibodies to Rickettsia typhi in the population indicated that murine typhus was common locally. This study indicates the need for further public health measures in the southern Sudan to control the spread of these infections.

Effect of viral infection on experimental allergic encephalomyelitis in mice

BALB/c mice were irradiated with 350 R and injected with mouse spinal cord homogenate (MSCH) in complete Freund's adjuvant. Only 15-30% of these animals developed signs of experimental allergic encephalomyelitis (EAE) at 21-28 days after inoculation. Intraperitoneal infection with the non-lethal A7 strain of Semliki forest virus (SFV) 7 days after sensitization reduced the mean appearance time of the EAE symptoms to 14 days and the number of animals with clinical EAE increased up to 70%. In contrast, virus inoculation 10 days before induction of EAE decreased significantly the incidence of clinical EAE in both BALB/c and SJL mice. Demyelination with increased cellularity, presence of macrophages, stripping of myelin from the axons and sparing of oligodendrocytes was observed in spinal cords of animals at days 13-16 after induction of EAE and subsequent virus infection. No demyelination was seen in specimens taken at the same time from mice inoculated with MSCH or SFV alone. Combined MSCH and virus inoculations induced changes in the general immune response which may be one of the major reasons for the increase or decrease in demyelination in this model.

Glomerulonephritis in the acute phase of Ross River virus disease (epidemic polyarthritis)

Hematuria and proteinuria were detected at the peak of symptoms in a case of Ross River virus (RRV) disease. No other infective cause was identified. A renal biopsy 28 days after the onset of nephritis showed mild mesangial proliferative changes and one segmental sclerotic lesion. Immunofluorescence showed widespread linear deposition of IgG in glomerular capillary walls with similar but weak staining for IgM, complement (C3) and fibrinogen; granular deposits of IgM and C3 in several arterioles; and IgM in a few mesangial cells. No electron-dense deposits were detected, nor was RRV antigen found in the renal tissue. Anti-glomerular basement membrane antibodies were not detected in the serum. Recovery from the renal disturbance was complete within three months although rheumatic symptoms persisted for 30 months.

Illness caused by a Barmah Forest-like virus in New South Wales

Barmah Forest virus, a recently-discovered arbovirus which belongs to the alphavirus genus of the family Togaviridae, has been shown to cause infections in humans in New South Wales. The present report documents three patients in whom Barmah Forest viral infection appears to have resulted in illness. Barmah Forest virus or a closely-related alphavirus may, as are several other alphaviruses, be pathogenic.

Predisposition to EAE induction in resistant mice by prior infection with Semliki Forest virus

The premise that acute non-fatal viral infections of the central nervous system (CNS) predispose to the subsequent development of chronic immune-mediated neurologic disease was investigated. Adult C57Bl/6 mice inoculated peripherally with 10(4) PFU of the A774 strain of Semliki Forest virus (SFV) develop a transient encephalomyelitis and sporadic (less than 20%) mild symptoms of paralysis with demyelination in the cerebellum from which they recover. Such recovered mice were found to develop signs characteristic of experimental allergic encephalomyelitis (EAE) 2 to 8 wk after either immunization with myelin basic protein (MBP) or receipt of 1 to 2 X 10(7) lymph node cells from MBP-primed syngeneic donors. These two methods of disease induction were unsuccessful when applied to normal B6 mice or those previously inoculated with noninfectious SFV. These findings suggest the possibility that virus-induced damage to CNS tissue may facilitate subsequent priming or clonal expansion of pre-existing myelin-reactive lymphoid cells.

Semliki Forest virus-induced, immune-mediated demyelination: adoptive transfer studies and viral persistence in nude mice

Adoptive transfer experiments in athymic nude mice demonstrated that the demyelination seen in the central nervous system (CNS) following Semliki Forest virus (SFV) infection was directly dependent upon sensitized T lymphocytes. Antibodies generated during the infection did not seem to be involved in the demyelination, but thymus-dependent antibodies (IgG) were responsible for the reduction of brain virus titres. In the absence of a T cell response and T cell-dependent antibody production, virus persisted in the CNS for several months. Despite persistence of high virus titres for this time, only mice eventually developing a CNS inflammatory response developed lesions of demyelination. In the absence of an inflammatory response no demyelination was apparent even after several months of persistent infection. Administration of anti-SFV hyperimmune serum intracerebrally to both infected and control mice did not produce demyelination but resulted in CNS tissue degeneration with marked pycnosis.

[Study of immunological mechanisms of action of temperature and emotional stress factors in experimental flavivirus infections]

The influence of two stress factors, sharp changes in temperature and hypokinesia, on the course of experimental tick-borne encephalitis and Langat virus infections in mice has been studied. The data obtained in this study indicate that both factors produce defects in T- and B-cell-mediated immunity, accompanied by the activation of asymptomatic infection and the decrease of the mean survival time in acute infection. These two stress factors, differing in their intensity and nature (physical and emotional), have been shown to produce the same effect on the course of acute and asymptomatic flavivirus infections. In the former case the mean survival time of the animals decreases, and in the latter case clinically manifest infection develops. Under the conditions of hypokinesia (or changes in temperature), the death rate among the animals infected with langat virus has been found to increase 3- to 4-fold in comparison with the controls, the mortality level in the groups subjected to different stress factors being the same.

Post-encephalitic epilepsy and arbovirus infections in an isolated rainforest area of central Liberia

Among a population of 4.436 Bassa, Kpelle and Mano people in the Gbawein and Wroughbarh Clan region of Grand Bassa Country, Liberia, 123 cases of epilepsy could be documented. In 38% of these cases infections involving the central nervous system precipitated the onset of seizures. Sera from 67 epilepsy patients, 50 direct healthy relatives and 22 geographically matched controls were tested for antibodies to 16 arboviruses of the Togaviridae and Bunyaviridae known to occur in Africa. Antibodies to arboviruses were found in 16.5% of the epilepsy patients, 36% of the mostly older family members, and in 22% of the controls. Males and females were equally affected as were the different clans and language groups. Although meningoencephalitis with sequelae, like seizures, are known to result from arbovirus infections, no evidence for a correlation between epilepsy in this are of Central Liberia and previous arbovirus infection could be established.

Ockelbo disease in Sweden: epidemiological, clinical, and virological data from the 1982 outbreak

An outbreak of Ockelbo disease, a syndrome with rash, arthralgia and moderate fever reactions, which occurred in Sweden 1982 is described. A virus, designated Edsbyn 5/82, isolated from mosquitoes and closely related to Sindbis virus (Togaviridae: Alphavirus) is the probable etiologic agent. Sixty-five patients with typical clinical manifestations of the disease became ill in August 1982 and exhibited antibody titer rises against both Edsbyn 5/82 and Sindbis viruses by indirect immunofluorescence and the mixed hemadsorption technique. With the latter method, but not by the neutralization tests, antibody titers were significantly higher against Edsbyn 5/82 virus than against Sindbis virus. Most cases occurred in central Sweden between the 60th and 63rd parallels. The frequency of antibody in healthy individuals (blood donors) within the endemic area was 2-3% and in foci with high incidence, antibody positivity reached 8%. Antibody frequencies continuously decreased south and north of this area. Antibody decline was followed in a group of 12 patients who had Ockelbo disease in 1981. Mixed hemadsorption titers were 4-6 times higher against Edsbyn 5/82 than against Sindbis virus. A 2- to 4-fold antibody decline took place from early convalescence to 20 months after onset.

Poliovirus infection of cyclophosphamide-treated mice results in persistence and late paralysis: I. Clinical, pathologic, and immunologic studies

An attenuated human poliovirus infection of cyclophosphamide (CY)-treated mice was developed as a model of persistent CNS enterovirus infections and as an investigation of the interaction of virus with motor neurons during persistence. Ten percent of mice inoculated intracerebrally with undiluted virus developed clinical disease by day 90, but of those treated with CY, 80% developed disease. At higher virus dilutions plus CY there was a marked increase in the incubation period. The latest onset of clinical disease occurred on day 146. Only paralyzed animals had pathologic changes in the spinal cord and virus antigen in anterior horn cells. Neutralizing antibodies were suppressed by CY, as were humoral and cellular immune responses to other antigens.

Epidemic polyarthritis in Australia, 1980-1981

Information concerning their clinical illness was obtained by self-administered questionnaire from 528 patients who suffered from epidemic polyarthritis in Australia during 1980 and 1981. The clear and uniform clinical picture which has emerged from this study should facilitate the diagnosis of this disease. The illness begins suddenly with the onset of acute aching in the muscles and joints, followed by a maculopapular rash in between 40% and 78% of patients, and extensive polyarthritis. This affects chiefly the ankles, fingers, knees and wrists, usually serially, but no joint is spared. Estimates of incubation time suggest that it ranges from three to 21 days (mean, nine days). Women, especially housewives, are the group most frequently affected. Exposure to mosquitoes is an important predisposing factor; the implications of this for prevention and future research are considered. The mechanism of the survival of the virus in nature remains poorly understood.

Chikungunya virus infection. A retrospective study of 107 cases

A retrospective study of 107 cases of serologically proven chikungunya (CHIK) virus infection was undertaken. All respondents had contracted the disease at least 3 years previously; 87,9% had fully recovered, 3,7% experienced only occasional stiffness or mild discomfort, 2,8% had persistent residual joint stiffness but no pain, while 5,6% had persistent joint pain and stiffness and frequent effusions. Synovial fluid from 3 patients was analysed. All the patients with persistent joint pain and stiffness had very high antibody titres against CHIK virus.

Ross River virus activity along the south coast of New South Wales

The sera of 468 blood donors and 63 domestic animals, collected from the south coast of New South Wales, were tested for the presence of antibodies to Ross River virus. Antibodies were detected in 7% of human sera, 25% of cow sera and 65% of horse sera. Using the blood donors as 'human sentinels', seroconversions were demonstrated in two donors from the Nowra-Kiama region and from a patient in the same area; none of the three had been outside of the study area during the period of seroconversion or at the time of infection. Of the 15 seropositive horses, 6 (40%) had lived continuously since birth on the farms on which they were bled. That humans and horses were infected with Ross River and not a related alphavirus was shown by microneutralization tests against Ross River virus and the other two alpha-viruses (Getah, Sindbis) known to occur in Australia.

Ross River virus-induced demyelination: I. Pathogenesis and histopathology

Ross River virus (strain T48) infection in mice causes an encephalomyelitis characterized by focal, primary demyelination in the cerebellum, brain stem, and spinal cord. Maximal serum and brain content of virus occurs on days 2 and 4, respectively. Virus is not detectable in serum after day 3 or in brain after day 9. Histopathological lesions are present by day 2 and consist of perivascular macrophage and polymorphonuclear leukocyte infiltration, focal necrosis in the internal granule cell layer, and myelin disruption. Mononuclear cell infiltrates are present by day 5. Foci of demyelination in the presence of preserved axons become more widespread by day 8, and early partial remyelination occurs by day 13. Immunosuppression reduces the mononuclear cell infiltration but does not alter the demyelination . Although the mechanism of Ross River virus-induced demyelination is not known, these findings suggest that it is not immune mediated.

Demyelination induced in mice by avirulent Semliki Forest virus. I. Virology and effects on optic nerve

Swiss A2G mice were infected intraperitoneally with an avirulent strain of Semliki Forest virus. The virus titres in the optic nerves, retina and brain were estimated on post-inoculation days 3 to 8. High titres of virus were obtained in the optic nerve, retina and brain. The optic nerves, retina and brain were studied by light microscopy up to post-inoculation day 67. Electron microscope studies wee carried out on the optic nerve on post-inoculation days 11 and 14. Inflammatory, microcystic changes and demyelination seen in the optic nerve were similar to those found in he central nervous system.

Zika virus, a cause of fever in Central Java, Indonesia

In 1977 and 1978 selected in-patients at the Tegalyoso Hospital, Klaten, Indonesia who had recent onsets of acute fever were serologically studied for evidence for alphavirus and flavivirus infections. A brief clinical history was taken and a check list of signs and symptoms was completed on admission. Acute and convalescent phase sera from 30 patients who showed evidence that a flavivirus had caused their illnesses were tested for neutralizing antibodies to several flaviviruses which occur in South-east Asia. Paired sera from seven patients demonstrated a fourfold rise in antibody titre from acute to convalescent phase. The most common clinical manifestations observed in this series of patients included high fever, malaise, stomach ache, dizziness and anorexia. None of the seven patients had headache or rash despite the fact that headache and rash had been associated with two of the three previously studied. The onsets of illness clustered toward the end of the rainy season when populations of Aedes aegypti, a probable vector in Malaysia, were most abundant.