Biomedical subjects

T Stroffolini

Publications and source records attributed to T Stroffolini.

At least 109 records · Page 6Linked to original sources

PubMed1991

Seroepidemiology of pertussis infection in an urban childhood population in Cameroon.

In 1989, the prevalence of IgG antibodies to pertussis toxin (PT) in a sample of 367 unvaccinated apparently healthy children 5-14 years old was estimated by ELISA in Kumba City (Cameroon). Children were recruited using a systematic random sampling from six primary schools located in different districts of the city. The sample was representative of the various socioeconomic classes. The overall prevalence was 75%; it increased from 62% in 5 year old children to 81% in children 12-14 years old (P less than 0.01). IgG antibody prevalence was positively related to the family size. Children belonging to households of nine or more members had a 2.2-fold risk (C.I. 95 per cent = 1.1-4.6) of previous exposure to B. pertussis infection. No association was found with the father's occupation (O.R. = 1). These findings demonstrate a great impact of pertussis infection in Cameroon, with a nearly total exposure by late childhood.

Adolescent↗

PubMed1991

Baseline sero-epidemiology of hepatitis B virus infection in children and teenagers in Italy. A survey before mass hepatitis B vaccination.

During the period May 1987 to November 1989, the prevalence of hepatitis B virus (HBV) markers was determined by ELISA in serum samples of 7405 (55% male, 45% female) apparently healthy persons 3-19 years of age in Italy. Earlier studies of adults there had shown an intermediate degree of HBV endemicity (hepatitis B surface antigen carrier rate greater than 2%). Persons were selected by systematic cluster sampling in five different geographical areas of Italy. The overall prevalence of hepatitis B surface antigen (HBsAg) was 0.6%. The overall prevalence of at least one marker of HBV was 2.8%; it increased from 1.7% among children 3-5 years of age to 4.5% in teenagers 17-19 years of age (P less than 0.001). The prevalence of any HBV marker was higher in southern then in northern areas (3.5% vs. 1.8%, P less than 0.001). A significant association was found with sociodemographic features. Persons whose fathers had less than 6 years of schooling had a 2.3-fold risk (C.I. 95% = 1.5-3.4) while those belonging to a household of six or more under one roof had a 1.7-fold risk (C.I. 95% = 1.2-2.4) of previous exposure to HBV infection. These findings indicate that, today in Italy, exposure to HBV infection at a young age is very low and suggest a shift towards a low degree of endemicity following improvements in socio-economic conditions, decreased family size and increasing use of disposable syringes during recent years.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1991

Immunity to diphtheria in the 3-19 year age group in Italy.

In Italy, immunization with diphtheria toxoid has been compulsory for all newborns since 1939. The last two clinical cases of diphtheria were reported in 1987. During the period 1987-1989, immunity against diphtheria was assessed by neutralization test in a random sample of 1740 healthy subjects 3-19 years old, from five geographical areas of Italy. Of the total population, 76.5% showed antibody levels considered to be protective (greater than or equal to 0.1 IU ml-1), 17.2% had a relative degree of protection (0.01-0.09 IU ml-1), and 6.3% lacked immunity (less than 0.01 IU ml-1). The percentage of unprotected subjects increased from 6.1% in the age group of 3-5 years to 11.4% in the age group of 18-19 years (p less than 0.01). A smaller proportion of males (5.3%) than of females (7.2%) was unprotected, but this difference was not statistically significant. Subjects residing in the south and the islands were more likely to be unprotected than those residing in the north (7.4 versus 4.1%, p less than 0.01). No association was found between lack of protective antibodies and family size (odds ratio 1.35, confidence interval 95% = 0.77-2.36). However, paternal education of less than 12 years was associated with a higher prevalence of non-responders. In order to maintain a high degree of immunity in the adult population, a routine adult booster dose of diphtheria toxoid is advisable.

Antibodies, Bacterial↗

PubMed1991

Prevalence of cytomegalovirus infection in Italy.

Between 1987 and 1989, the prevalence of antibody to cytomegalovirus (CMV) was determined, by the ELISA method, in serum samples from 1494 apparently healthy subjects, 3-18 years old. Subjects were selected by a systematic cluster sampling from five geographical areas in Italy. The overall prevalence of antibody was 64.2%, increasing from 54.4% in 4-6-year-olds to 73.3% in subjects 17-18 years old (P less than 0.01). Prevalence of antibody was significantly higher in females (P less than 0.05) and in subjects residing in the South of Italy (P less than 0.01). A significant association was found with sociodemographic factors. Subjects belonging to a household with six or more persons had a 1.5-fold risk (C.I. 95% = 1.11-2.04) and subjects whose fathers had less than 6 years of schooling had a 1.4-fold risk (C.I. 95% = 1.1-1.87) of previous exposure to CMV infection. The high prevalence (74.4%) of young women who are naturally immune when entering childbearing years does not guarantee that there will be a low risk of fetal infection.

Adolescent↗

PubMed1991

Age- and sex-related study of HBV-DNA in HBsAg asymptomatic children from an endemic area (Cameroon).

A sero-epidemiological survey was carried out in Cameroon in January 1989 on a sample of 702 children of primary school age. A high HBV endemicity level was observed: 60.3% of the sera were positive to any HBV marker, 23.2% (163 sera) were HBsAg-positive. HBV-DNA positivity was observed in 38/163 (23.3%), thus showing a high level of infectivity among these carriers. Seventy-seven HBsAg-positive sera were tested for HBeAg/anti-HBe: 20 (26%) were HBeAg-positive 31 (40%) anti-HBe-positive, and 26 (34%) were negative for both. All sera were anti-HD-negative. Twenty-five per cent of HBeAg-positive sera were HBV-DNA-negative. This finding could be explained by a delayed HBeAg/anti-HBe seroconversion phase with fluctuant HBV-DNA. Only one case of HBV-DNA-positive anti-HBe-positive serum was observed. This study showed that HBV-DNA prevalence was significantly higher in boys (31.8%) than in girls (14.1%) (p less than 0.02). This difference was not observed for any HBV marker. We therefore conclude that in boys a prolonged HBV replicative phase might explain the observed high chronicity rate.

Age Factors↗

PubMed1991

Clonotypic analysis of human antibodies specific for Neisseria meningitidis polysaccharides A and C in adults.

Serum antibodies to the capsular polysaccharides A and C (PSA and PSC) of N. meningitidis in healthy adults before and after vaccination with the sole polysaccharides were analysed by isoelectric focusing (IEF). Before vaccination, 49% and 28% had naturally acquired antibodies against PSA and PSC, respectively, whereas 18 days after vaccine administration 84% and 91%, respectively, showed a detectable spectrotypic pattern. Oligoclonality appeared to be the main feature of naturally acquired and vaccine-induced antibodies for both polysaccharides. In all subjects the anti-PSA response, showing dominant bands at the same pH position, was more homogeneous than anti-PSC one. Most subjects with naturally acquired antibodies (25 out of 38 for PSA and 20 out of 22 for PSC) showed a spectrotypic pattern after vaccination, similar to that observed before vaccination (any differences were just related to band intensity), suggesting that PSA and PSC are able to recruit the same B cell clones previously primed with a T-dependent form of the antigen, i.e. the whole bacterium. However, in one-third of subjects with naturally acquired anti-PSA antibodies, the appearance of new alkaline bands after vaccination was observed. Furthermore, in subjects with absence of detectable natural antibodies, the vaccine-induced antibody response started in correspondence of alkaline pH areas, subsequently extending to neutral and acidic areas. Therefore, it may be hypothesized that alkaline antibody-secreting B cell clones are the first to be recruited. The final spectrotype in these subjects was similar to that observed in subjects with naturally acquired antibodies. This observation, together with the above reported data, allow us to conclude that natural (T-dependent pathway) and vaccine (T-independent pathway) immunization induce the expression of the same antibody repertoire, for both meningococcal PSA and PSC.

Adolescent↗

PubMed1991

Age-specific prevalence of hepatitis A virus infection among teenagers in Sardinia.

In 1989, the prevalence of antibodies to hepatitis A virus (anti-HAV) in a sample of 1350 Sardinian teenagers aged 14 to 19 years was estimated by Elisa method. The overall anti-HAV prevalence was 20%; it increased from 12.3% among 14-16 year old subjects to 27.4% in subjects aged 17-19 years (P less than 0.01). A slight female preponderance was observed (22.1% versus 17.9) but no statistically significant difference was attained. Compared with the corresponding figure (71.6% of prevalence rate) observed in North Sardinia in 1980, the results of the present study show a dramatic reduction in anti-HAV prevalence among teenagers. A significant association was found with sociodemographic factors: subjects whose fathers had less than six years of schooling, had a 2.1-fold risk (C.I. 95% = 1.5-3.1) and subjects belonging to a household of 6 or more under one roof had a 1.7-fold risk (C.I. 95% = 1.2-2.3) of previous exposure to hepatitis A virus (HAV) infection. These findings indicate that exposure to HAV in Sardinia is decreasing, probably because of improvements in socio-economic conditions during recent years. However, overcrowding and short paternal education appear to be important determinants of infection.

Adolescent↗

PubMed1991

A high degree of exposure to hepatitis A virus infection in urban children in Cameroon.

In January 1989, the prevalence of antibodies to hepatitis A virus (anti-HAV) was determined by ELISA in 702 apparently healthy children 5-14 years old in Kumba City, Cameroon. Children were recruited from those attending six different primary schools, representative of the socio-demographic characteristics of the inhabitants, using a systematic random sampling. The overall IgG anti-HAV prevalence was 96.9%, reaching 100% by the age of 11 years. In primary school beginners the prevalence was very high, 94.0%, contrary to what has been observed in developed countries. The anti-HAV prevalence was not associated with family size, but was related to parent's occupation, children from the lower class having a 5.9 fold risk (C.I. = 1.9-18.3) of past exposure to HAV. These results suggest a persistently high prevalence of anti-HAV in children despite improving hygienic conditions. The spread of HAV in this population may be the result of domestic water and/or food contamination.

Adolescent↗

PubMed1991

Hepatitis-C virus infection in Italy: a multicentric sero-epidemiological study (a report from the HCV study group of the Italian Association for the Study of the Liver).

To assess possible geographical differences in the spread of hepatitis-C virus (HCV), the prevalence of antibodies against HCV (anti-C-100-3) was investigated in various adult population groups in 29 centres in Italy. Anti-HCV was positive in 375 out of 28,433 voluntary blood donors (1.3%): prevalence was higher in southern Italy (1.51%) than in the northern regions (1.28%), but the difference was not statistically significant. Anti-HCV prevalence was similar in the north and south in post-transfusion chronic hepatitis (91%), haemophiliacs (73%), intravenous drug users (70%), and haemodialysis patients (28%), where parenteral contacts are obvious, and in HBsAg carriers (14%), a group with evidence of previous parenteral contamination. In contrast, anti-HCV prevalences were found to be significantly higher in the south than in the north and central Italy among patients with hepatocellular carcinoma (HCC) (73 vs 59%), cryptogenic liver disease (67 vs 58%), autoimmune chronic hepatitis (72 vs 44%) and alcoholic liver disease (51 vs 34%). These results indicate a very high circulation of HCV in Italy, with maximum incidence in the south and in the islands. They suggest that its spread in the community can occur through inapparent parenteral routes as observed for hepatitis-B (HBV) and hepatitis-delta viruses (HDV) and possibly facilitated by poorer social-demographic and life-style factors.

Adult↗

PubMed1991

Meningococcal disease in Italy in 1990.

The incidence of meningococcal disease in Italy in 1990 was 0.5/100,000 in the general population and 0.7/100,000 in army recruits. The highest proportion of cases (32%) was seen in subjects 1-4 years old. The sex ratio was 1.0 Serogroup B constituted 72% of the isolates; 16% belonged to group A and 12% belonged to group C. The proportion of strains resistant to suphonamides was 56%, while no strain was resistant to minocycline or rifampicin. Two secondary cases, but no comprimary cases occurred among civilians. The predominance of serogroup B and the further decline in military cases constitute the findings of major interest.

Adolescent↗

PubMed1991

Prevalence of Toxoplasma gondii antibodies among children and teenagers in Italy.

Between 1987 and 1989, the prevalence of antibodies to Toxoplasma gondii was determined by ELISA in serum samples from 1,494 apparently healthy subjects, 3-18 years old. Subjects were selected by a systematic cluster sampling from five geographical areas in Italy. The overall prevalence of antibodies was 17.9%, increasing from 4.7% in 4-6 year olds to 28.4% in 17-18 year olds (P less than 0.01). A slight predominance was observed among males (18.2% vs. 17.5% in females), as well as among subjects residing in Southern Italy and the Islands (21.9% vs. 19.2% in subjects residing in the North), but neither difference was statistically significant. Toxoplasma infection was associated with sociodemographic factors. Subjects belonging to a household with six or more persons had a 1.8-fold risk (C.I. 95% = 1.3-2.6) and subjects whose fathers had less than six years of schooling had a 2.7-fold rosk (C.I. 95% = 1.8-3.9) of previous exposure to toxoplasma infection. Considering the large proportion (70%) of young women entering childbearing age without toxoplasma antibodies, it appears that the risk of congenital toxoplasmosis will not be negligible in Italy in forthcoming years.

Adolescent↗

PubMed1990

An outbreak of hepatitis A in young adults in central Italy.

Between September, 1988 and January, 1989 a common source outbreak of 47 cases of serologically confirmed hepatitis A occurred in a town of central Italy. Thirty-eight cases were primary, three co-primary and six secondary. The highest age-specific attack rate was seen in subjects aged 15-24 years (120 per 100,000); the mean age of cases was 24.6 years and the median age was 22 years. A matched triplet case-control study showed significant association between the disease and consumption of either raw mussels (41% of cases, compared with 10% of controls; P less than 0.0001) or a single brand of mineral water (63% of cases, compared with 41% of controls; P less than 0.05). The mean age of the cases reflects the shift in primary susceptibility to the infection from younger to older age groups, a finding which has recently been demonstrated by several seroepidemiological surveys in Italy.

Adolescent↗

PubMed1990

Changing patterns of hepatitis A virus infection in children in Palermo, Italy.

In 1988 in Palermo, Italy, the prevalence of antibodies to hepatitis A virus (anti-HAV) in a sample of 490 children 6-13 years old was 10.6%; it increased from 6.3% among children 6-10 years old to 14.7% in children 11-13 years old (P less than 0.01). Compared with findings from a survey conducted in 1978 in the same area, the results of the present study show a significant (P less than 0.01) reduction in the anti-HAV prevalence in both age groups. Anti-HAV prevalence was inversely related to the father's years of education and positively related to the family size. Children of fathers with less than 6 years of schooling had a 3.2-fold risk (C.I. 95% = 1.3-8.1), and children with five or more members in their households had a 2.7-fold risk (C.I. 95% = 1.1-6.4) of previous exposure to hepatitis A virus (HAV) infection. Our findings indicate that exposure of children in Palermo to HAV is decreasing significantly, probably because of improvements in socio-economic conditions during recent years; however socio-demographic factors appear to be important determinants of infection.

Adolescent↗

PubMed1990

Trends in meningococcal disease in Italy in 1988.

Meningococcal disease in Italy decreased 15% in 1988 from the previous year (290 vs. 342 cases). The decline was particularly evident in military cases (1.7/100,000 in 1988 vs. 5/100,000 in 1987) reflecting the full coverage of bivalent serogroup (A + C) meningococcal polysaccaride vaccine in army recruits, achieved since January 1988. The highest proportion of cases was seen in people older than 25 years of age (25%). Serogroup C constituted 60% of the isolates, while 19% belonged to serogroup B. The proportion of strains resistant to sulphonamides was 45%, while 15% were resistant to Minocycline and none to Rifampin. Out of the five military cases, only one (due to serogroup C) was attributable to the vaccine failure. A single coprimary case, but no secondary cases occurred among civilians. These findings are consistent with the trends reported in Italy in the previous years.

Adolescent↗

PubMed1990

Vaccination campaign against meningococcal disease in army recruits in Italy.

A high attack rate (17.3/100,000) of meningococcal disease in army recruits in Italy, with 95% of the cases due to serogroup C, constituted the motivating factors to make bivalent serogroup A + C meningococcal vaccination compulsory by law for army recruits starting January 1987. Because the vaccine was given only to the new recruits entering the army, full coverage was not achieved until January 1988. Nearly 900,000 subjects (300,000 yearly) were vaccinated between January 1987 and December 1989. There were no reports of any untoward reactions to the vaccine. Of the 300,000 recruits in service each year, 52, 21, 15, 5 and 4 cases of the disease occurred in 1985, 1986, 1987, 1988 and 1989, respectively (P less than 0.001). Of the 24 cases occurring since the start of the vaccination, only two (due to serogroup C) were attributable to vaccine failure. The remaining cases were in unvaccinated recruits (15 cases) or were due to serogroups other than A or C (7 cases). The cumulative incidence of meningococcal serogroup C in the 600,000 vaccinated recruits during the period 1988-89 was 0.2/100,000 (1 case amongst 600,000 recruits), while the corresponding figure in the 600,000 unvaccinated recruits during the period 1985-6 was 11.3/100,000 (68 cases amongst 600,000 recruits) (P less than 0.001). The protective efficacy of the vaccine in 1987 was 91.2% (12 cases of meningococcal serogroup A and C disease from an average of 150,000 unvaccinated recruits observed for 1 year, and 1 case from the corresponding average of 150,000 vaccinated ones). In 1988 and in 1989 this figure could not be calculated because all recruits were vaccinated.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1990

Age-specific prevalence of hepatitis B virus infection among children in an endemic area in southern Italy.

In 1989 the prevalence of hepatitis B virus markers was studied by radioimmunoassay in a sample of 1,426 healthy children, 3 to 11 years old, attending kindergarten and the primary schools in a large urban area of the Apulia Region in Southern Italy, where the hepatitis B surface antigen (HBsAg) prevalence among pregnant women is 5.6%. The overall prevalence of any hepatitis B virus marker was 3.4%, increasing from 1.7% in 3- to 5-year-old children to 5% in 10- to 11-year-old children (P less than 0.002). Prevalence was not associated with the father's years of schooling (odds ratio, 1.98; confidence interval, 95% (0.9 to 4.6] or with the family size (odds ratio, 2.96; confidence interval, (0.7 to 11.8]. The overall HBsAg prevalence was 0.8, a rate that was lower than the 5.6% found in pregnant women. The finding of only 12 HBsAg-positive children of the 1,426 tested, despite 80 of them being born to HBsAg-positive carrier mothers (on the basis of the 5.6% HBsAg prevalence among pregnant women), is probably attributable to the low proportion (5%) of hepatitis B e antigen positivity among the HBsAg-positive carrier mothers in the study area. The observed low HBV infection rate in younger age groups, which confirms recent studies in other areas of Italy, appears to be the result of several factors: improved socioeconomic conditions; decreased family size; and increased use of disposable syringes in the last few years.

Age Factors↗

PubMed1990

Genomic fingerprints and phenotypic characteristics of strains of Neisseria meningitidis causing disease in Italy.

Since 1984 a change in the epidemiological pattern of meningococcal disease in Italy has occurred with a predominance of Neisseria meningitidis of serogroup C (76%), serotype 2a and a high proportion of strains resistant to sulfonamides (71%). To better understand the epidemiology of the group C N. meningitidis strains responsible for the disease over the last five years in Italy, we studied the DNA fingerprinting of 62 strains in combination with serotyping and sulfonamide susceptibility testing. The results show that the phenotypical features as well as the fingerprints of the strains studied were similar, suggesting the spread of a single clone in the patients studied. This is in agreement with the circulation of strains typical of epidemic situations, despite the decreasing incidence of the disease in Italy during the examined period.

DNA, Bacterial↗

PubMed1990

The effect of meningococcal group A and C polysaccharide vaccine on nasopharyngeal carrier state.

The effect of Neisseria meningitidis group A and C polysaccharide vaccine on nasopharyngeal carriage was studied in Italian army recruits. Throat swabs were cultured for N. meningitidis at the time of vaccination (one week after entry to service) and again three weeks later in a follow-up cohort of 98 men. At the first survey the overall carriage rate was 32% with 9% of isolates due to serogroup C, none to serogroup A and 17% to serogroup Y. At the second survey the overall carriage rate reached 52% (P less than 0.01); no isolate belonged to serogroup A or C, while serogroup Y reached 40% (P less than 0.01). The cumulative carriage rate was 65%. Out of the 64 carriers during the whole study period, only 7 (11%) belonged to the same serogroup during the two different surveys. The vaccination appears to influence the carriage rate of meningococcal specific serogroups. The inhibition of serogroups A and C is, however, offset by an increased prevalence of meningococci belonging to serogroup Y.

Bacterial Vaccines↗