A study of Coxsackie B virus infections, 1972-1983

The Enterovirus Theory of Disease Etiology in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Critical Review

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a complex, multi-system disease whose etiological basis has not been established. Enteroviruses (EVs) as a cause of ME/CFS have sometimes been proposed, as they are known agents of acute respiratory and gastrointestinal infections that may persist in secondary infection sites, including the central nervous system, muscle, and heart. To date, the body of research that has investigated enterovirus infections in relation to ME/CFS supports an increased prevalence of chronic or persistent enteroviral infections in ME/CFS patient cohorts than in healthy individuals. Nevertheless, inconsistent results have fueled a decline in related studies over the past two decades. This review covers the aspects of ME/CFS pathophysiology that are consistent with a chronic enterovirus infection and critically reviews methodologies and approaches used in past EV-related ME/CFS studies. We describe the prior sample types that were interrogated, the methods used and the limitations to the approaches that were chosen. We conclude that there is considerable evidence that prior outbreaks of ME/CFS were caused by one or more enterovirus groups. Furthermore, we find that the methods used in prior studies were inadequate to rule out the presence of chronic enteroviral infections in individuals with ME/CFS. Given the possibility that such infections could be contributing to morbidity and preventing recovery, further studies of appropriate biological samples with the latest molecular methods are urgently needed.

Covid-19 systemic infection exacerbates pre-existing acute disseminated encephalomyelitis (ADEM)

Acute disseminated encephalomyelitis (ADEM) is an uncommon diagnosis in adults. It is known to be due to an abnormal immune response to a systemic infection rather than direct viral invasion to the central nervous system. There have been few reports of ADEM diagnosed in the setting of COVID-19 systemic infection. However, we report a case of Coxsackie induced ADEM that remitted but got exacerbated by COVID-19 infection. The patient contracted the COVID-19 infection shortly after being discharged to a rehabilitation facility. Direct COVID-19 neuroinvasion was ruled out via CSF PCR testing for the virus. The patient responded well to pulse steroid therapy and plasmapheresis in both occasions. We hypothesize that COVID-19 infection can flare-up a recently remitted ADEM via altering the immune responses. It is known now that COVID-19 infection can produce cytokine storming. Cytokine pathway activation is known to be involved in the pathology of ADEM. Caution regarding discharging immune suppressed patient to the inpatient rehabilitation facility should be made in the era of COVID-19 pandemic.

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COVID-19 infection can exacerbate an acute disseminated encephalomyelitis (ADEM) attack.

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Early recognition of ADEM in the setting of COVID-19 is crucial for early treatment.

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Treated ADEM exacerbated by COVID-19 systemic infection carries a good prognosis.

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Diagnosis of COVID 19-exacerbated ADEM depends on CSF viral testing.

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Alternative methods to inpatient skilled nursing rehabilitation should be considered.

EV71 infection correlates with viral IgG preexisting at pharyngo-laryngeal mucosa in children

Enterovirus 71 (EV71) infection causes severe central nervous system damage, particularly for children under the age of 5 years old, which remains a major public health burden worldwide. Clinical data released that children may be repeatedly infected by different members in enterovirus and get even worsen. Mucosa, especially epithelium of alimentary canal, was considered the primary site of EV71 infection. It has been elusive whether the preexsiting viral antibody in mucosa plays a role in EV71 infection. To answer this question, we respectively measured viral antibody response and EV71 RNA copy number of one hundred throat swab specimens from clinically confirmed EV71-infected children. The results released that low-level of mucosal IgG antibody against EV71 broadly existed in young population. More importantly, it further elucidated that the children with mucosal preexsiting EV71 IgG were prone to be infected, which suggested a former viral IgG mediated enhancement of viral infection in vivo.

The association between prior infection with five serotypes of Coxsackievirus B and incident type 2 diabetes mellitus in the EPIC-Norfolk study

AIMS/HYPOTHESIS

Infections with Coxsackieviruses have been linked to beta cell dysfunction. Given the importance of beta cell dysfunction in the aetiology of type 2 diabetes, we hypothesised that prior infection with Coxsackieviruses B would increase the risk of type 2 diabetes. The aims of the study were to estimate cross-sectional associations between potential predictors of previous infection and seropositivity for Coxsackievirus B serotypes 1-5 (CBV1-5), and then to assess the association between seropositivity and incident type 2 diabetes.

METHODS

Using a case-cohort design nested within the European Prospective Investigation of Cancer (EPIC)-Norfolk study, we ascertained n = 603 cases of incident type 2 diabetes. From within the entire cohort we identified a random subcohort of n = 835, without diabetes at baseline. The presence of Coxsackievirus B neutralising antibodies against serotypes 1-5 was assessed using a plaque neutralisation assay. Weighted Cox regression was used to examine the association between presence of antibodies to CBV1-5 and the development of type 2 diabetes.

RESULTS

Seropositivity in the subcohort for CBV1-5 was 50%, 67%, 66%, 75% and 45%, respectively. After adjustment for age, sex, BMI, physical activity and family history of diabetes, the presence of antibodies against CBV1-5 was not associated with incident type 2 diabetes, over a mean follow-up of 5.7 years (HR [95% CIs] 0.94 [0.72,1.25], 0.92 [0.68, 1.23], 1.33 [0.98,1.81], 1.16 [0.83,1.61] and 1.03 [0.77,1.39] for CBV1-5, respectively).

CONCLUSIONS/INTERPRETATION

The presence of antibodies against any of five serotypes of Coxsackievirus B was not associated with incident type 2 diabetes.

Chronic fatigue syndrome

During the past two decades, there has been heated debate about chronic fatigue syndrome (CFS) among researchers, practitioners, and patients. Few illnesses have been discussed so extensively. The existence of the disorder has been questioned, its underlying pathophysiology debated, and an effective treatment opposed; patients' organisations have participated in scientific discussions. In this review, we look back on several controversies over CFS with respect to its definition, diagnosis, pathophysiology, and treatment. We review issues of epidemiology and clinical manifestations, focusing on the scientific status of CFS. Modern neuroscience and genetics research offer interesting findings for new hypotheses on the aetiology and pathogenesis of the illness. We also discuss promising future issues, such as psychopathophysiology and mechanisms of improvement, and suggest multidisciplinary prospective studies of CFS and fatigue in the general population. These studies should pay particular attention to similarities to and differences from functional somatic syndromes and other fatiguing conditions.

Association of type 2 diabetes mellitus and seroprevalence for cytomegalovirus

BACKGROUND

Infection is known to play a role in type 1 diabetes, but there is a paucity of information on its role in diabetes mellitus type 2. We examined the seroprevalence of selected viruses in a group of predominantly Hispanic patients with type 2 diabetes and control subjects without diabetes.

METHODS

One hundred thirteen patients, 83 with type 2 diabetes and 30 control subjects, all undergoing hemodialysis at the same facility in San Antonio, Texas, were tested for antibodies against coxsackie B viruses, cytomegalovirus (CMV), and parvovirus. Sixty-six of these patients and 25 control subjects were tested bimonthly for 6 months.

RESULTS

We observed a greater seroprevalence of anti-CMV IgG antibodies among patients with diabetes (97.6%), compared with control subjects (86.7%), and the difference was statistically significant [OR = 6.2, 95% CI: 1.1 to 36.0, P < 0.05]. Three draws on a subset of 91 patients produced still greater odds [OR = 12.4, 95% CI: 1.3 to 117, P < 0.05]. There were significantly more (P < or = 0.001) vascular complications among patients with diabetes. There was a colinearity of trends between diabetes, seropositivity to CMV, and age.

CONCLUSIONS

Our findings indicated an up to 12 times greater odds of having type 2 diabetes for persons previously exposed to CMV. Since accelerated atherosclerosis is also associated with diabetes and CMV, past CMV infection may be a common factor that links atherosclerosis and diabetes. No other viruses tested in this study, either coxsackie B viruses or parvovirus, showed a significant association with type 2 diabetes.

Enteroviruses as agents of emerging infectious diseases

Although the enteroviruses as a group are ubiquitous and not normally considered as "emerging pathogens," the many different serotypes circulate at different frequencies in any given year and the prevalence of a given serotype may fluctuate wildly from year to year. As a result, several enterovirus serotypes have been associated with the emergence of specific diseases (for example, pandemic acute hemorrhagic conjunctivitis) and specific serotypes have emerged to cause outbreaks of major public health concern. Enterovirus 71 is a recognized cause of epidemic severe central nervous system disease in Southeast Asia. Acute hemorrhagic conjunctivitis was a newly described disease in the 1970s associated with emergence of enterovirus 70 and coxsackievirus A24 variant. In addition, the impending eradication of poliovirus and some of the challenges currently faced by the eradication program present the possibility that poliomyelitis could emerge in the posteradication era. These links between enterovirus infections and emerging diseases are reviewed.

Meta-analysis of the association of enteroviruses with human heart disease

The role of viruses in the genesis of both dilated cardiomyopathy (DCM) and acute myocarditis remains uncertain. Modern molecular techniques such as polymerase chain reaction (PCR) and in situ hybridisation are sensitive means of detecting viral genomic material in human myocardial tissue and may help to resolve the quest. Meta-analysis of the papers in the literature records studies of both acute myocarditis and DCM where molecular techniques were used to demonstrate enteroviruses. This review studies information from the published literature as well as statistical analysis of the cumulative molecular data relating enteroviruses to DCM, and to compare these findings with the information available on the role of enteroviruses in acute myocarditis. Twelve papers reported studies in acute myocarditis, of which 11 found higher percentages of enteroviral RNA positivity in the diseased population, giving an overall odds ratio of 4.4. Seventeen papers reported studies in DCM, with 11 recording higher positivity rates in these patients. Cumulative analysis of these data suggests an overall odds ratio of 3.8. The causative role of enteroviruses in acute myocarditis, particularly in children, is supported by meta-analysis of the available literature. The data on DCM is suggestive of an association but a proportion of the studies are negative.

Comparison of coxsackie B neutralisation and enteroviral PCR in chronic fatigue patients

Coxsackie B enteroviruses have been implicated repeatedly as agents associated with chronic fatigue syndrome (CFS). The objective of this study was to compare the serological evidence for the presence of Coxsackie B virus neutralising antibody, with the polymerase chain reaction (PCR) detecting a portion of the 5' nontranslated region (NTR) of the enterovirus genome. Serum samples from 100 chronic fatigue patients and from 100 healthy comparison patients were used in this study. In the CFS study group, 42% patients were positive for enteroviral sequences by PCR, compared to only 9% of the comparison group. Using the neutralisation assay, 34% of study patients were positive, compared to 41% of comparison patients. In the study group, 66/100 patient results correlated, i.e., they were either positive/positive or negative/negative for both tests. Of those that did not correlate, the majority were PCR-positive/Coxsackie B antibody-negative (21/34). In the comparison group, 58/100 patient results correlated. Of those that did not, the majority were PCR-negative/Coxsackie B antibody-positive (37/42). The Coxsackie B antibody neutralisation assay was not able to differentiate the CFS study group from the healthy comparison group, and thus the clinical relevance of this assay may be questioned. The PCR assay did differentiate the two groups with significantly more CFS patients having evidence of enterovirus than the comparison group.

Analysis of protein synthesis by two-dimensional gel electrophoresis in T cells persistently infected with coxsackie B virus

Coxsackie B viruses (CBV) have been implicated in various human diseases that present as either limited acute infections or prolonged chronic infections. A number of investigations have suggested that a virus-induced immune dysfunction might play a role in in vivo pathogenesis. In the current study, we describe CBV infection of two human T cell-derived cell lines (Jurkat and MOLT-4 cells) as potential models for CBV infection of lymphocytes. Short term (up to 144 h post-infection) CBV infection of either cell line resulted in a decline in the viability of the cell population together with an approximate 10-fold rise in the titre of infectious virus during the period of incubation. Analyses of the intracellular proteins by two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) demonstrated that although putative virus proteins were detectable there was minimal inhibition of the cellular protein synthesis following CBV infection. This contrasted with the more permissive and highly lytic CBV infection of HEp-2C cells (Cash, Electrophoresis 1991, 10, 793-800). Persistently infected cell lines from both Jurkat and MOLT-4 cells (piJURKAT-3673 and piMOLT-2667 cells) were established. Analyses of intracellular protein synthesis of these persistently infected cell lines showed the synthesis of novel proteins not detected for the corresponding uninfected parental cell line. There were no significant alterations in overall cellular protein synthesis detectable by the small format 2-D PAGE system employed in these investigations. The data presented in the current investigation will contribute towards studies on virus-induced responses of specific biological functions associated with T cells.

Detection of enterovirus-specific RNA in serum: the relationship to chronic fatigue

The serum of 88 chronic fatigue patients was screened for enteroviral specific sequences by polymerase chain reaction (PCR) assay. The PCR method used was "nested" PCR targetting the 5' nontranslated region of the enteroviral genome which yielded a final fragment length of 264 base pairs. Samples were obtained from patients during 1990-1991. In addition, buffy coat specimens and stool specimens were examined in some patients. Samples from two cohorts of comparison individuals were also obtained. The comparison groups were firstly, acutely ill individuals with symptoms consistent with a presumed enteroviral infection (matched by age, sex, and date of receipt of specimen) and secondly, healthy individuals (matched by age and date of receipt of specimen). Enteroviral specific sequences were detected in 36 of 88 serum samples from chronic fatigue patients, 22 of 82 acutely ill individuals, and 3 of 126 healthy individuals. The enteroviral PCR positivity did not correlate with any one particular feature of chronic fatigue nor did it reflect any history of illness at onset of fatigue, duration of fatigue, or age of patient. These results provide new evidence for the presence of enteroviral specific sequences in serum, buffy coat, and stool samples in many patients with chronic fatigue. This may reflect a persistent enterovirus infection in a proportion of chronic fatigue patients.

Coxsackie virus infections in rheumatic fever

The close relationship between Group A beta Hemolytic Streptococci (GABS) and rheumatic fever is a well established one. However, the concept of the streptococcus as the sole etiologic agent of the rheumatic heart disease (RHD) has been challenged over the past years. Since coxsackievirus group B (CVB) has long been proposed as a cause of acquired valvular disease simulating rheumatic fever, we attempted in this study to document infections with this group of viruses in patients with rheumatic fever. We obtained blood samples from 106 patients with old (quiescent) rheumatic fever/rheumatic heart disease [group I], 94 patients with acute rheumatic fever (ARF) [group II], and 74 normal matched controls. We tested for the presence of neutralizing antibodies to the 6 serotypes of CVB by a micro neutralization test. We have found that infection with CVB, especially types B2 and B4, was common in the studied population. Forty-two percent of normal individuals had evidence of infection with any of the 6 serotypes of CVB. Patients of group I had significantly more frequent infections with CVB 2. Patients in group II had significantly more frequent infections with CVB 2 and CVB 6. There was no clear correlation between such infections and the clinical course of rheumatic fever. There was no difference in the incidence of CVB infections between patients with definite ARF, and patients with suspected ARF. We set a low order association between rheumatic fever and infection with CVB types B2 and B6. We emphasize the importance of pursuing the investigation of the role of CVB in relation to RHD.

Limb paralysis as a manifestation of Coxsackie B virus infection

Forty-four African children (25 girls, 19 boys) are described with single or multiple limb paralysis as a manifestation of infection with Coxsackie B virus. Single limb paralysis involved exclusively the lower extremity, with no nervous system involvement elsewhere and a relatively benign prognosis. Multiple limb paralysis occurred either alone or with other neurological deficits. Only two of 15 patients followed up for five months or longer regained premorbid motor status. Seven patients required assisted ventilation, of whom all but one died. Viral infection remains an important cause of acute limb paralysis in this population, and Coxsackie B is the agent often responsible.

Studies on the epidemiology of child infections in the Bari area. I. Current state of immunity against Coxsackie B viruses

The presence and titer of neutralizing antibodies against Coxsackie B viruses were investigated in 1,944 children under 15 years of age living in Bari and its area. In 1,781 out of 1,944 sera (91.6%), neutralizing antibodies were present against at least one of the strains tested: 333 (17.1%) samples were found to be positive for one serotype only, 412 (21.2%) for 2 serotypes, 394 (20.3%) for 3, 394 (18.0%) for 4, 199 (10.2%) for 5 and 94 (4.8%) for all 6 strains tested. Of the 1,944 serums examined, 1,043 (53.7%) were found to be positive for type 2, 1,073 (53.3%) for type 5, 991 (51.0%) for type 1, 858 (44.1%) for type 3, 760 (39.1%) for type 4 and 605 (31.1%) for type 6. The rate of positive responses, which was high at birth and in the first months of life (96.7%), diminished between 6 months and 1 year (81.7%) and then rose according to age until it reached 97.7% between 10 and 11 years. After that we observed a considerable reduction in the serological positivities (i.e. 82.3% between 11 and 12 years and 81.5% between 12 and 13 years, respectively).

Evidence for a group-specific enteroviral antigen(s) recognized by human T cells

Human peripheral blood mononuclear cells from 15 normal, healthy adult volunteers proliferated in vitro against a panel of enteroviral antigens, including coxsackievirus B3, coxsackievirus B2, coxsackievirus B6, coxsackievirus A16, and poliovirus 1. No proliferation against the cardiovirus encephalomyocarditis virus occurred. Lymphocytes obtained from cord blood drawn from seven neonates were uniformly nonresponsive to enteroviral antigens. Although serum neutralization antibody titers indicated different exposure histories of the volunteers, only one had a titer against coxsackievirus B6, a rare isolate in the United States. The peripheral blood mononuclear cells from each volunteer responded in vitro to each enterovirus tested even though not all individuals had serum neutralizing antibody against each virus. The predominant cell type responding in vitro was the CD4+ T cell. Denaturation of viral antigen by Formalin did not prevent the recognition of the common group antigen by the T cells, indicating that noninfectious virus can also serve as antigen. These data demonstrate that human T cells recognize a common enterovirus group antigen(s).

Myalgic encephalomyelitis--a persistent enteroviral infection?

Myalgic encephalomyelitis is a common disability but frequently misinterpreted. Amongst 6,000 patients referred for general microbiological diagnosis between 1975 and 1987, 420 cases were recognized. Coxsackie B neutralization tests, in 205 of these, demonstrated significant titres in 103/205 (50%), while of 124 additionally investigated for enteroviral IgM, 38/124 (31%) were positive. This illness is distinguished from a variety of other post-viral states by an unique clinical and epidemiological pattern characteristic of enteroviral infection. Prompt recognition and advice to avoid over-exertion is mandatory. Routine diagnosis, specific therapy and prevention, await further technical advances.

Molecular approaches to enteroviral diagnosis in idiopathic cardiomyopathy and myocarditis

Enteroviruses are thought to be etiologic agents in some cases of human myocarditis and dilated cardiomyopathy. Murine models of acute coxsackievirus B3 myocarditis implicate coxsackie B viruses as possible causes of human myocarditis. Indirect evidence implicating enteroviruses as causative agents in human heart disease derives from serologic studies. More recently, direct evidence for enteroviral presence in diseased human heart tissues has been obtained by nucleic acid hybridization analyses. Although the data suggest that enteroviral infections may be associated with 18% to 50% of cases of myocarditis or dilated cardiomyopathy, or both, causality has not been established. Unanswered questions remain regarding the specific identity of the enteroviral genomes detected in the human heart and the potential for enteroviruses to persist in the heart.

Secondary enterovirus infection in the murine model of myocarditis. Pathologic and immunologic aspects

Enteroviruses are implicated as etiologic agents in the inflammatory diseases myocarditis and polymyositis. In this report, we show that a previous enterovirus exposure in mice can influence development of myocardial inflammation with a second enteroviral exposure. Inoculation of 25-day-old male C3H/HeJ mice with 10(3) or 10(5) plaque-forming units (PFU) of infectious or ultra violet (UV)-inactivated coxsackievirus B2 (CVB2), followed by inoculation 28 days later with 10(5) PFU of a myocarditic variant of coxsackievirus B3 (CVB3-m) results in more intense myocardial inflammation and injury than is seen in age-matched mice inoculated with CVB3-m alone. More severe disease occurs with the lower primary dose of CVB2. Neutralizing antibody to CVB2 is detected early after primary inoculation and neutralizing antibody to CVB3 is first detected 5 days after secondary inoculation. In vitro proliferation of splenocytes from mice inoculated with one or both viruses occurs in response to both CVB2 and CVB3 antigens. We recently demonstrated that murine T cells are capable of recognizing an enterovirus group antigen. Thus cell-mediated immune responses to a conserved antigenic epitope(s) among the enteroviruses may be involved in the exacerbation of myocardial inflammatory disease during a second enterovirus infection. The secondary infection model described here may more accurately mirror virus-induced myocarditis in the human population because the majority of adults have been exposed to several enteroviruses before induction of disease.

Features of Coxsackie B virus (CBV) infection in children with prolonged physical and psychological morbidity

A retrospective study of the clinical features in 39 children who were investigated for evidence of Coxsackie B virus (CBV) infection is reported. Eighteen children were found to have serological evidence of infection. An extensive range of features was elicited in both seropositive and seronegative patients, most children complaining of abnormalities referable to muscle and, in particular, of weakness and easy fatiguability. Children with evidence of CBV infection were significantly more likely to belong to social classes I and II, to have relatives with serological evidence of CBV infection, and to show certain dysphoric features as well as to complain of sore throats. The relationship between CBV infection and 'myalgic encephalomyelitis' or 'post-viral syndrome' is discussed, and it is suggested that these descriptions are inappropriate given our current knowledge, and inadequately describe the clinical features seen in the children under study. An alternative description, 'fatigue-dysphoria syndrome' is proposed.

Coxsackie B viruses and myalgic encephalomyelitis

Data collected over the past 6 years suggest that Coxsackie B viruses (CBV) play an important role in myalgic encephalomyelitis (ME). Since psychological upset is a feature of this illness, 247 patients, recently admitted to a psychiatric hospital, were tested for neutralizing antibodies to CBV. A total of 12.5% had significantly raised CBV titres compared with 4-5% of 'well' control groups; the percentage positive was greatest (21%) in those aged 30-39 years. During 1985 and 1986 sera from 290 adults with ME were tested using the newly developed CBV IgM ELISA test; 37% were CBV IgM positive compared with 9% of 500 'well' adult controls. Forty-seven children, with ME were similarly tested during this period; 38% were positive, implying recent or active CBV infection. The combined use of this ELISA test and the virus probe techniques now available should further help to elucidate the exact role of CBV in this disabling illness.

Coxsackie B viruses and the post-viral syndrome: a prospective study in general practice

In a prospective study sera from 140 patients with symptoms suggesting a post-viral syndrome and sera from 100 controls were tested for neutralizing antibodies to Coxsackie B viruses. Sixty-five of the patients (46%) and 25 of the controls (25%) had significant antibody titres. The 65 positive cases who had presented with symptoms were followed up and retested six months later and again after one year. Of these 65 patients 36 (55%) were still unwell after one year and high antibody titres persisted in all but two of the patients. Recovery was not found to correlate with a fall in antibody level, but was more rapid in patients whose presenting symptoms were paraesthesiae, anorexia or dyspnoea. The importance of correctly identifying patients with the post-viral syndrome, who may otherwise be labelled neurotic, is emphasized.

Routine use of mu-antibody-capture ELISA for the serological diagnosis of Coxsackie B virus infections

The role of coxsackie B viruses (CBV) in myo/pericarditis has been well documented; however, interpretation of static high neutralising antibody titres in individual patients has always been difficult. In introducing the mu-antibody capture ELISA test for the detection of CBV-specific IgM, we hoped to overcome this problem. A regimen for the routine serological diagnosis of CBV infections was introduced, using the CBV IgM ELISA as a screening test, followed by neutralisation tests (NT) to confirm the positive results. Seven hundred and sixty patients and 304 healthy adult controls were tested. The percentage CBV IgM positive in each of the clinical categories myo/pericarditis (33%) chest pain (22%), myalgic encephalomyelitis (31%), myalgia/Bornholm (19%) and controls (9%) was similar to those found in previous studies using NT alone. Cross-reactions with other enteroviruses, including hepatitis A (Enterovirus 72), were observed but did not prove to be a problem in the illness studied, since most involved adults. Both homotypic and heterotypic CBV IgM responses were found. Matching IgM and NT indicated a recent CBV infection. Positive IgM with negative NT titres suggested a recent infection with an enterovirus other than a CBV.

Epidemic Coxsackie B virus infection in Johannesburg, South Africa

A particularly extensive epidemic of Coxsackie B3 virus infection occurred in Johannesburg in the spring and summer of 1984. A total of 142 positive cases were diagnosed by isolation of the virus from stools and other specimens (60) or by serology (82). Coxsackie B3 accounted for 87% of the isolations and was also the dominant serotype on serology. The outbreak involved predominantly children and young adults, with no apparent sex differences being noted. The majority of specimens came from the white population and no significant difference in age or sex distribution could be observed between the two race groups. The major clinical presentation in the white group was Bornholm disease followed by cardiac involvement and then meningoencephalitis. In the black group, however, myocarditis was the major clinical presentation, which is of particular interest taking into account the extremely high incidence of acute rheumatic carditis in this population and the prevalence of chronic cardiomyopathy.