Safety and immunogenicity of hepatitis A vaccine in infants: a candidate for inclusion in the childhood vaccination programme.

Forty-eight infants received a single dose (720 ELISA units = 0.5 ml) of inactivated hepatitis A vaccine at the fifth month of age with booster at the 11th month of age, together with the second and third doses of the vaccines compulsory under Italian law (diphtheria, tetanus, oral polio and hepatitis B). Overall, the seroconversion rate was 100%. The anti-HAV geometric mean titre (GMT) reached 3,021 mIU/ml in infants born to anti-HAV-negative mothers, but only 399 mIU/ml in infants born to anti-HAV-positive mothers. Hepatitis A vaccine was immunogenic, safe and well tolerated without significant side-effects. There seems to be no reason for not including it in childhood vaccination programmes particularly in low endemic HAV areas.

Persistence of anti-HBs in children vaccinated against viral hepatitis B in the first year of life: follow-up at 5 and 10 years.

The persistence of anti-HBs protective levels in groups of children who had been immunized against Hepatitis B 5 and 10 years earlier, in their first year of life, has been studied. The results were analyzed according to the type of vaccine (both plasma-derived and DNA recombinant) and the number of doses administered (three or four doses). In addition, the protective effect of the vaccine in vaccinated subjects was studied in relation to the anti-HBc presence. The serologic results suggest that, in cohorts of children vaccinated 5 years earlier, a higher prevalence of subjects with anti-HBs protective levels was found, when the DNA recombinant vaccines were administered (97.6% for MSD Recombivax and 97.1% for SKF Engerix B); a lower one when the plasma-derived vaccine was used (80.4% Pasteur Merieux, Hevac B). Moreover, in cohorts of children vaccinated with plasma derived vaccine (hevac B) 10 years earlier, a higher prevalence of subjects with anti-HBs protective levels was demonstrated when four doses were administered (76.9%); a lower one when three doses were inoculated (57.5%). The absence of core antibody (anti-HBc) in responders to the vaccination shows the protective efficacy of both the DNA recombinant and plasma derived vaccines. On the other hand the presence of anti-HBc in some anti-HBs negative non-responders subjects shows the susceptibility of these people to infection. In anti-HBs negative vaccinated subjects the appearance of levels of anti-HBs in 95.9% of subjects, 1 week after the administration of a booster dose, demonstrates the presence of a solid immunologic memory.

Effective antibody response in newborn babies living in Maldives to simultaneous vaccination against hepatitis B, poliomyelitis, diphtheria and tetanus.

The antibody responses of Maldivian infants early in their life to simultaneous immunization against hepatitis B virus, poliomyelitis, diphtheria and tetanus were investigated. The vaccines were given at 6, 10 and 14 weeks of age. Among 243 newborn babies from HBsAg-negative mothers, 103 received three doses of oral poliomyelitis (OPV) and diphtheria and tetanus (DTV) vaccines; 105 were similarly immunized but received in addition the recombinant hepatitis B vaccine (HBV); 35 were immunized with the HBV recombinant vaccine alone. The antibody response to all of the vaccines was effective. No significant differences among the groups were observed. Hepatitis B vaccination of infants neither affected nor was affected by the contemporary administration of OPV and DTV vaccines.

Detection of hepatitis C virus-RNA by polymerase chain reaction in dental surgeries.

The mean prevalence of anti-hepatitis C virus (HCV) in Italy is 0.87%. It reaches 2% in Campania, Southern Italy. Approximately 50% of community acquired non-A, non-B (NANB) hepatitis cannot be associated with known parenteral exposure. A recent Italian study has shown that the only demonstrable risk factor in 9% of acute C/NANB hepatitis is dental treatment. There are no data on direct contamination by HCV of dental surgeries. Possible environmental contamination by HCV-RNA was investigated in dental surgeries after treatment of anti-HCV and HCV-RNA positive patients. Thirty-five anti-HCV and HCV-RNA positive patients with chronic hepatitis underwent dental treatment and were enrolled in this study. Eight had chronic persistent hepatitis (CPH), 23 chronic active hepatitis (CAH), and 4 cirrhosis. A total of 328 samples collected from instruments and surfaces were tested after dental treatment of 35 anti-HCV positive patients. The presence of HCV-RNA was determined by polymerase chain reaction (PCR) to evaluate contamination of instruments and surfaces in dental surgeries. Twenty (6.1%) out of 328 collected samples were positive for HCV-RNA. The positive samples were from work benches (two), air turbine handpieces (one), holders (four), suction units (one), forceps (four), dental mirrors (two), and burs (six). Our data indicate that there is extensive contamination by HCV of dental surgeries after treatment of anti-HCV patients and that if sterilisation and disinfection are inadequate there is the possible risk of transmission to susceptible individuals.

HCV-RNA survival as detected by PCR in the environment.

We have shown that HCV-RNA is resistant to drying at room temperature for at least 48 hours. This is a factor which could influence the diffusion of the virus in the general population, which epidemiological studies have shown to be surprisingly high. It should be considered in evaluating the importance of the inapparent parenteral routes of transmission.

Blood in saliva of patients with acquired immunodeficiency syndrome: possible implication in sexual transmission of the disease.

The presence and concentration of haemoglobin in saliva of anti-human immunodeficiency virus (HIV) positive subjects, anti-HIV-negative subjects at high risk of infection, and healthy controls were studied. One hundred eighty-eight subjects were anti-HIV-positive intravenous drug abusers (IVDA), 22 were anti-HIV-positive homosexual men, 23 were anti-HIV-positive heterosexual contacts, 132 were anti-HIV-negative IVDA, 35 were anti-HIV-negative homosexual men, and 154 were healthy controls. Two milliliters of saliva was collected in the morning before brushing teeth, and the presence and the concentration of haemoglobin were determined. Based on hemoglobin, the data show that the anti-HIV-positive IVDA have the highest tendency to bleeding. The difference between this group with respect to anti-HIV-negative IVDA (P < 0.05) and compared with healthy controls (P < 0.01) is statistically significant. This is also true of anti-HIV-positive heterosexual contacts with respect to healthy controls (P < 0.01). Our data show that all at-risk groups, both anti-HIV positive and anti-HIV negative, have higher haemoglobin concentration than the control group; this difference reaches statistical significance only between anti-HIV-positive IVDA and controls (P < 0.01). The concentration of haemoglobin is significantly higher in subjects with CD4+ lymphocytes < 200/mm3 compared to subjects with CD4+ lymphocytes > 200/mm3 (P < 0.01), in subjects with AIDS-related complex (ARC)/AIDS compared to asymptomatic/PGL subjects (P < 0.01), and in subjects with stomatitis compared to subjects without stomatitis (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

[Demonstration of the interchangeability of 2 types of recombinant anti-hepatitis-B vaccine]. / Dimostrazione dell'interscambiabilita' dei due tipi di vaccino anti-epatite B DNA-ricombinante.

A vaccination cycle cannot always be completed with the same type of vaccine with which it was initiated because the same type of vaccine is not always available at the vaccination centers. For this reason we have verified the possibility of substituting one of two anti hepatitis B DNA-recombinant vaccines [Engerix B (SK&F); Recombivax HB (MSD)] both available in Italy in the vaccination protocol. A study was performed on 480 subjects using both types of DNA recombinant vaccine and on 160 using only one type of vaccine. Our data show that there is no difference in immunogenic potency of the two DNA recombinant vaccines available in Italy and that a cycle begun with one vaccine can be completed with the other with no effect on the percentage of seroconversion or the mean anti-HBs titre.

[Adaptability of the anti-hepatitis-B vaccine Recombivax HB to the Piazza protocol for the mass vaccination of newborn infants]. / Adattabilità del vaccino anti-epatite B Recombivax HB allo "schema Piazza" per la vaccinazione di massa dei nuovi nati.

27 healthy babies born to HBsAg, antiHBs and antiHBc negative mothers were given three doses of hepatitis B vaccine "Recombivax HB" (5 micrograms/dose/0.5 ml) at 3, 5 and 11 months of age (Piazza's protocol). AntiHBs response was highly satisfactory. Since both in terms of seroconversion rate and of mean antiHBs titre immunogenicity of other hepatitis B vaccines given at 3, 5 and 11 months of age was already demonstrated, it is possible to conclude that Piazza's protocol is valid for all hepatitis B vaccines available in Italy and will certainly facilitate the compulsory hepatitis B vaccination in infants in Italy.

A pilot model of vaccination against hepatitis B virus suitable for mass vaccination campaigns in hyperendemic areas.

A hepatitis B vaccination campaign was carried out in a town of 60,000 inhabitants, Afragola, Campania, Italy, a hyperendemic area for hepatitis B where HBsAg prevalence was 13.4% and anti-HBc prevalence was 64.7%. This experimental pilot project aimed to reduce the incidence of both acute and asymptomatic viral hepatitis B and of related chronic liver complications. From 1983-1989, 8,400 subjects were vaccinated: 6,900 children up to 10 years of age and 1,500 subjects from 11-60 years of age. High seroconversion rates were observed: 99.0% in all children under one year of age, 96.0% in the older children, and 86.7% in adults. The rate of infection in Afragola has diminished from 63/100,000 in 1983 to 10/100,000 in 1989. Carriers of HBsAg decreased in the general population (7.3% compared to 13.4%), especially in children up to 10 years of age (1.0% compared to 9.0%). In babies who received hepatitis B vaccine at the same time as compulsory vaccinations compliance was 98% while it was 80% in babies who were vaccinated separately. In June 1991 the Italian Parliament promulgated a decree which imposes hepatitis B vaccination for all newborn babies at 3, 5, and 11 months of age, at the same times as the mandatory childhood vaccinations (diphtheria, tetanus, and polio) according to a new protocol (Piazza scheme) which has been in use since January 1987 in our pilot vaccination campaign in Afragola.

Blood in saliva of HIV seropositive drug abusers: possible implication in AIDS transmission.

We have studied hemoglobin concentration in saliva of anti-HIV positive and anti-HIV negative intravenous drug abusers (IVDA) and normal controls and the relationship between hemoglobin concentration in saliva and number of CD4+ cells and clinical status of AIDS in anti-HIV positive IVDA. 120 anti-HIV positive IVDA, 112 anti-HIV negative IVDA and 116 normal healthy subjects not belonging to any risk group for HIV infection completed the study. Saliva was collected at awakening before brushing teeth and the concentration of hemoglobin was determined. Hemoglobin concentration in saliva in basal conditions is higher in anti-HIV positive IVDA with respect to anti-HIV negative IVDA (p less than 0.05) and controls (p less than 0.01). In anti-HIV positive IVDA hemoglobin concentration in saliva is higher in subjects with CD4+ cells less than 200/10(6) l with respect to subjects with CD4+ greater than 200/10(6) l (p less than 0.05) and in subjects with ARC/AIDS with respect to subjects with PGL or who are asymptomatic (p less than 0.01). Subjects with ARC/AIDS have a mean concentration of hemoglobin of 19 micrograms/0.1 ml saliva (range 0-153) which corresponds to 1.3 microliters of blood/ml saliva. If 10 ml of saliva are exchanged during kissing an average of 13 microliters of blood are transferred (110 microliters of whole blood at extreme range). Blood of symptomatic patients has an HIV titer of 7 TCID/microliters which for 10 ml saliva containing an average of 1.3 microliters blood/ml saliva corresponds to an average of 90 TCID (770 TCID at the extreme range).(ABSTRACT TRUNCATED AT 250 WORDS)

A modified immunisation schedule for the hepatitis B vaccine Recombivax HB suitable for mass vaccination in childhood.

Following the demonstration of a fully satisfactory immunogenic activity of a hepatitis B vaccination protocol consisting of three doses of Hevac B Pasteur vaccine given at 3,5 and 11 months of age, it was possible to administer this vaccine at the same times as the vaccinations for diphtheria, tetanus and polio which are mandatory in Italy at those ages. We have also shown that both another plasma-derived vaccine, H-B-VAX (MSD), as well as the DNA-recombinant Engerix B (SK&F) are highly immunogenic when given at the same times as the mandatory childhood vaccinations. In this paper we demonstrate that the same schedule can be used for another hepatitis B vaccine prepared by a DNA-recombinant technique, Recombivax HB (MSD) recently introduced in Italy. In fact two doses of this vaccine, the first given at three months of age and the second two months later, resulted in a 100% seroconversion rate and a mean anti-HBs titre of 440 mUI/ml. Although the date are incomplete since the third dose will be given at 11 months of age, we conclude that this hepatitis B vaccine can also be used in the mass vaccination campaigns of infants in Italy, the first of which was initiated in January 1987 in an hyperendemic area near Naples (HBsAg prevalence about 14%). We underline that this mass vaccination campaign is the first in Europe.

Immunogenicity of a DNA-recombinant hepatitis B vaccine (Engerix B) given at 3, 5 and 11 months of age with a new schedule suitable for mass vaccination programmes.

Following the demonstration of a fully satisfactory immunogenic activity of a hepatitis B vaccination protocol consisting of three doses given at the 3rd and 5th months of age with a booster at 11, it was possible to administer this vaccine at the same times as the vaccinations for diphtheria, tetanus and polio which are mandatory in Italy at those ages. A field trial of this protocol in a hyperendemic area near Naples (prevalence of HBsAg about 14%) started on January 1987. The French vaccine, Hevac B, Pasteur, was used. At this time compliance is 99%, and fully satisfactory results both in terms of seroconversion rate (96.3%) and of mean anti-HBs titre (4,352 mIU/ml) two months after the booster dose have been obtained. In this paper we demonstrate that even for a new hepatitis B vaccine prepared by a DNA-recombinant technique (Engerix B, SK & F) recently introduced in Italy, the same schedule can be used. In fact two doses of this vaccine, the first given at three months of age and the second two months later, resulted in a 100% seroconversion rate and a mean anti-HBs titre of 560 mIU/ml. Two months after the booster given at 11 months of age the mean anti-HBs titre was 12,100.