Adenovirus 7 (Ad7) is the adenovirus species that most frequently has been associated with severe illness. Seven distinct genome types of adenovirus 7, Ad7p, Ad7a, Ad7b, Ad7c, Ad7d, Ad7e, and Ad7f, can be identified by using restriction endonucleases BamHI and SmaI. We analyzed the distribution of the different Ad7 genome types among 314 isolates from patients and healthy shedders. The Ad7b and Ad7c genome types accounted for 90% of the isolates from patients and appeared to be mutually exclusive. A shift from Ad7c to Ad7b genome types occurred in 1969 in Europe and in 1975 in Australia. During the last decade, Ad7b genome types predominated in Australia, Europe, and North America. Ad7c was detected in South Africa, Ad7d was detected in China, Ad7e was detected in Brazil, and Ad7f was detected in Australia. The Ad7p and Ad7a genome types dominated among isolates obtained from healthy shedders and appeared scattered through the years and the geographical areas. The prevalence of Ad7 infections is high in Japan as judged by the herd immunity. However, the low percentage (2%) of Adi isolates among all adenovirus isolates chiefly from patients, coupled with 30 to 50% antibody prevalence, argues for a high proportion of inapparent infections and, hence, Ad7 strain(s) of low pathogenicity.

No abstract

Twenty-six strains of faecal adenovirus from three continents (two from Europe, 16 from South Africa, and eight from Canada) were typed as Ad40 by restriction enzyme analysis of the DNA using Sma I. The DNA of the strains was further compared by digestion with six other enzymes, namely Bam HI, Eco RI, Bgl I, Xho I, Sst I, and Hind III. At least two different restriction profiles were found to exist for each enzyme. Nineteen of the 26 strains studied had the same combination of profiles for all the enzymes, within the limits of resolution of the technique. This genome type was detected from all three continents and included the Finnish reference strain Hovi-X. The other seven strains were genome variants, representing five other genome types. Three genome types were detected only in South African specimens, whereas one genome type was detected in single specimens from both South Africa and Canada. Strain Dugan from Holland, indistinguishable from other Ad40 strains in neutralization tests using polyclonal antibody preparations [de Jong et al, 1983], deviated from the common Hovi-X-like genome on digestion of the DNA with any of the enzymes except Sma I.

A cohort of children from Gaza was observed from birth to the age of one year. Blood specimens were collected at birth, before and after poliovirus vaccination and at one year of age. Poliovirus immunity before and after vaccination was assessed by ELISA and virus neutralization (NT). Positive predictive values for ELISA were between 81.5% and 90.8%. However, ELISA revealed a high frequency of false negatives, and unacceptably low negative predictive values between 28.6% and 55.4%. The history of poliovirus immunity in the cohort was further investigated by NT. A high level of seropositivity to poliovirus type 1 (PV-1) was found. In cord blood, 83.3% had a NT titre greater than or equal to 4 and 99.0% had a titre greater than or equal to 2. Similarly, by one year of age, 85.7% had a titre greater than or equal to 4 and 90.5% had a titre greater than or equal to 2. Seropositivity to PV-2 and PV-3 were slightly lower, ie 80.8% of children had a PV-2 titre greater than or equal to 4 and 75.4% had a PV-3 titre greater than or equal to 4. As for other developing areas, poliomyelitis eradication in Gaza will come about when universal vaccination fills all 'immunity gaps' and improved sanitation and housing reduces the endemicity of wild polioviruses.

publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. 925 epidemiological grounds that they repeated themselves in tandem over many years in many countries-but what little doubt2 there may have been now seems removed. All sera and CSFs were also tested for NT to three types of poliovirus and the EH-24 variant strain of Coxsackie A24 virus, which causes clinically similar conjunctivitis.3 However, our results clearly indicated that these viruses had nothing to do with the 1981 epidemic of AHC or its neurological complications in Bombay (data not shown).These are very preliminary observations, as we have yet to analyse the bulk of the material available.