P. J. Hugo Johansson

The throat : An important site for MRSA colonization

In order to evaluate the value of bacterial cultures taken from the throat, 266 patients with MRSA were retrospectively assessed. At the time when MRSA was first detected in the patient, the most frequent sites positive for MRSA were a skin lesion (110 patients, 41%), the anterior nares (109 patients, 41%), and the throat (102 patients, 38%). In 26%, 17%, and 17% of the patients, a skin lesion, the anterior nares, and the throat, respectively, were the only site where MRSA was seen. In 123 patients cultured for MRSA because of a close contact with an already known MRSA patient, 65 patients (53%) were positive for MRSA in their throat and in 40 patients (33%), throat was the only sample site with MRSA at the time when the patient was found to be MRSA positive. 146 of the 266 patients (55%) were colonized with MRSA in the throat any time throughout the period they were MRSA positive. We conclude that throat is an important reservoir for MRSA and that samples taken from the throat should be included in screening patients for MRSA.

A nosocomial sapovirus-associated outbreak of gastroenteritis in adults.

The human caliciviruses norovirus and sapovirus are leading causes of acute, non-bacterial gastroenteritis. In contrast to norovirus, sapovirus is known to give infections mainly in infants and young children. We describe a nosocomial outbreak of gastroenteritis associated with sapovirus involving 23 adult patients and medical staff. The mean age of the patients and medical staff was 52 y and the major signs and symptoms were nausea, diarrhoea, vomiting, abdominal cramp, headache, myalgia and fever. More patients had diarrhoea (72%) than vomiting (56%) and the mean duration of symptoms was 6 d. A secondary attack rate of 45% was seen affecting in all 10 persons with a mean age of 29 y. Sequences of the capsid gene revealed a 97% nucleotide homology to the sapovirus genogroup IV reference strain Chiba/000671T/1999. This is one of the first reported nosocomial outbreaks of sapovirus infection among adults and shows that a diagnostic test for sapovirus should be included in investigation of gastroenteritis among adults.

Food-Borne Outbreak of Gastroenteritis Associated with Genogroup I Calicivirus

ABSTRACT An outbreak of gastroenteritis affecting 158 of 219 (72%) guests and employees at a hotel is described. Food served at the hotel restaurant is believed to have been the source of the outbreak and to have been contaminated by sick employees working in the restaurant. A secondary attack rate of 22% was seen involving 43 persons in all. In stool specimens from seven of eight patients, Norwalk-like viruses (NLVs) were detected by electron microscopy. While NLV-specific PCR using primers JV12 and JV13 were negative, all specimens examined with primers NVp69 and NVp110 were positive. The failure of primers JV12 and JV13 was attributed to several mismatches in the JV12 primer. Genotyping and sequence analysis revealed that all samples had identical sequences and clustered with genogroup I, and the most closely related well-characterized genotype is Desert Shield. This is the first described food-borne outbreak associated with genogroup I virus in Sweden.

High prevalence of MRSA in household contacts.

In a 6-y period, 114 household contacts connected to newly diagnosed MRSA patients screened for MRSA in the southern part of Sweden. In 22 of 51 (43%) families, 1 to 4 household contact(s) connected to a MRSA patient were positive for MRSA. In the 22 families, 42 of 60 (70%) household contacts were positive for MRSA and transmission of MRSA occurred between adult couples, parents and children, grandparent and children and between siblings. Within a family, MRSA-positive family members had in all but 1 instance identical MRSA strain genotypes (spa types) making intrafamilial spread of MRSA highly probable. MRSA transmission among household contacts may contribute to the prevalence of MRSA in the community and failure to identify MRSA in household contacts may maintain MRSA colonization in an already known MRSA patient. MRSA screening of family members living in the same household as a known MRSA patient should therefore be considered.

Reovirus type 1 associated with meningitis

A previously healthy 3-month-old girl presented with symptoms of meningitis, diarrhoea, vomiting and fever. Green monkey kidney (GMK) cells inoculated with cerebrospinal fluid (CSF) revealed reovirus-like particles by electron microscopy. RNA-gel electrophoresis, immunofluorescence and virus neutralization identified the pathogen isolated from CSF as reovirus type 1. Antibody determination by immunofluorescence of paired sera showed a significant antibody titre rise to the CSF isolate and neutralization test revealed a greater than 4-fold antibody titre rise to the CSF isolate. The CSF isolate was also neutralized by reovirus type 1 antibodies. This report represents one of a few associating reovirus with CNS symptoms in humans.

Binding of human and animal immunoglobulins to the IgG Fc receptor induced by human cytomegalovirus

Human cytomegalovirus (HCMV)-infected cells express a virus-encoded receptor that is able to bind the Fc part of IGG: Some basic binding properties of this Fc receptor (FcR) have been examined. The affinity constant (K(a)) for human IgG Fc fragment in its interaction with acetone-fixed, HCMV-infected human embryonic lung fibroblasts was estimated to be around 2 x 10(8) M(-1) and the number of binding sites was estimated to be around 2 x 10(6) per cell. Of the human IgG, IgA, IgM and IgD classes, only IgG reacted with the receptor, and all four of the IgG subclasses were reactive. IgG from rabbit, hamster, cat, swine and horse exhibited binding to the HCMV FcR, in contrast to IgG from mouse, rat, guinea pig, dog, sheep, goat, cow and chicken. Immunoglobulins with and without HCMV IgG FcR-binding properties, like IgG from rabbit and mouse, can be of value in revealing the functional importance of the receptor. When the immunoglobulins were tested against herpes simplex virus type 1-induced FcR, both similarities and differences in immunoreactivity were seen relative to the HCMV FcR, which makes it unlikely that the binding sites for these two herpesvirus FcRs on the IgG molecule are identical.

Septicemia in Granulocytopenic Patients: A Shift in Bacterial Etiology

35 episodes of septicemia in 33 patients occurred among 269 consecutive patients with granulocytopenia (granulocyte cell count less than or equal to 0.5 x 10(9)/l) during the 7-year period 1982-1988. 59% of isolated bacteria were Gram-positive (Staphylococcus aureus, Staph. epidermidis, Streptococcus species and Pneumococcus) and 41% Gram-negative (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Enterobacter, Acinetobacter and Citrobacter). Compared to the 7-year period 1975-1981, there was a decrease in the relative number of patients with Gram-negative septicemia. Thus, a shift from a predominating Gram-negative etiology in the 1975-1981 period to a predominating Gram-positive etiology in the 1982-1988 period was noted. In both periods the mortality rate was high in patients with Gram-negative septicemia, especially in patients with a Ps, aeruginosa infection.

Hepatitis E Virus Infections in Patients with Acute Hepatitis non-A-D in Sweden

A total of 12 patients previously treated for acute hepatitis of unknown aetiology were retrospectively found to be anti-hepatitis E virus (HEV) IgG-positive. Four patients were anti-HEV IgM- and IgG-positive consistent with an acute HEV infection. All 4 had travelled to or were immigrants from HEV-endemic countries. One anti-HEV IgM-negative patient seroconverted from anti-HEV IgG-negative to positive and 3 from anti-HEV IgG-positive to negative in 2 consecutive serum samples. Of the remaining 4 patients without anti-HEV IgM, 3 had a history of recent travel to an HEV-endemic country. Most patients were young adults and all but 1 recovered from the hepatitis. One patient with a fulminant hepatitis was anti-HEV IgG-positive when tested 4 months after a journey to Turkey. She died from her fulminant hepatitis shortly after admission. All the other patients but 1 normalized their serum liver enzymes within 1-2 months after the onset of disease.

Severe Pasteurella multocida infections in pregnant women

We report 2 cases of severe infections due to Pasteurella multocida, both occurring during pregnancy in previously healthy women. Both women had contact with animals (dog and cat) but neither of them had been bitten. Apart from a slight decrease in IgG levels, no immunological defects could be detected. Both women had received oral phenoxymethylpenicillin in the early phase of the disease, but still fell ill with severe infections. One woman had meningitis while the other suffered from cellulitis with deep abscess formation.

Nosocomial transmission of Legionella pneumophila to a child from a hospital's cold-water supply.

Human Legionella infections mainly consist of community-acquired and nosocomial pneumonia and rarely affect children. We describe a nosocomial infection with Legionella pneumophila, serogroup 1, subgroup OLDA, in an immunocompromized 2-y-old girl at a paediatric clinic. L. pneumophila identical to that of the patient was found in the hospitals cold-water but not in the hot-water distribution system. Transmission of Legionella to the girl most probably occurred by Legionella-contaminated cold water mixed and heated by water from the hot-water system. Mixing of hot and cold water probably occurred through thermostatic water mixing valves connected to showers regulated by a handle at the shower head. Nosocomial Legionella infection might thus have occurred, although circulating hot water temperatures never dropped below 53°C and cultures for surveillance of Legionella from central parts of the hot-water system have been consistently negative. Legionellae were successfully eliminated from the hospitals cold-water distribution system by hot water flushing at 73°C for 1h.