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T Vesikari

Publications and source records attributed to T Vesikari.

At least 91 records · Page 5Linked to original sources

Clinical trials of rotavirus vaccines.

The clinical efficacy of candidate rotavirus vaccines has been tested in Tampere, Finland, over four winter and spring rotavirus epidemic seasons in 1983-1986. Testing against natural challenge has demonstrated that heterologous oral rotavirus vaccines induce cross-protection to human rotavirus diarrhoea. The trials have also given insight into mechanisms of protection in human rotavirus diarrhoea. After the oral vaccination of infants aged six to 12 months the highly attenuated bovine rotavirus strain RIT 4237, titre 10(8) per dose, probably 'takes' in most vaccinees, producing a symptomless intestinal infection with a low virus excretion rate and an antibody response in over 80% of the initially seronegative subjects. Upon natural challenge such vaccination gives no protection against human rotavirus infection but gives 50-60% protection against any clinically detectable rotavirus-associated illness and 80-90% protection against severe rotavirus diarrhoea, regardless of the infecting human rotavirus serotype. The less attenuated rhesus monkey rotavirus RRV-1, titre 10(5)-10(6) per dose, is more infectious in humans, and virus multiplication in the intestine results in excretion of vaccine virus in the stools and some clinical symptoms, mainly fever, 3-4 days after vaccination. The degree of protection against human rotavirus diarrhoea appears similar to that induced by bovine rotavirus vaccine.

Antibodies, Viral↗

Detection of serum antibody responses to RIT 4237 rotavirus vaccine by ELISA and neutralization assays.

Immunoglobulin class-specific determination by ELISA and a virus neutralization test (NT) were compared for the detection of the serum antibody responses after vaccination of infants with the RIT 4237 rotavirus vaccine (of bovine origin). A capture method was applied for specific IgM determination by ELISA because of its greater sensitivity and reproducibility over the conventional ELISA-IgM test. NT was improved through the use of an enzyme-labelled antibody for the detection of non-neutralized virus. In 6-12-month-old children, the most sensitive single test to detect an antibody response was the ELISA-IgM capture method, but the combination of ELISA-IgM and IgG tests or ELISA-IgM and NT detected the highest seroconversion rate of 79%. In newborn infants high levels of maternal antibody made the ELISA-IgG test unsuitable. ELISA-IgM gave a response rate of 31%, but NT with homologous virus was the most sensitive indicator of a serological response to the vaccine in this age group, yielding a 45% response rate.

Antibodies, Viral↗

Immunogenicity and safety of a low passage level bovine rotavirus candidate vaccine RIT 4256 in human adults and young infants.

A candidate rotavirus vaccine RIT 4256, derived from Nebraska calf diarrhea virus by 21 tissue culture passages, was tested in humans and compared with the RIT 4237 vaccine derived from the same stem virus by 147 tissue culture passages. The low passage strain RIT 4256 was first tested in adult volunteers for immunogenicity and safety: a serological response was seen in 9/18 (50%) vaccinees; three subjects had a mild fever reaction attributable to the vaccine. In 6 month old children the RIT 4256 vaccine elicited a serological response in 12 of the 21 (57%) seronegative recipients; two children had a possible fever reaction from the vaccination. In newborn infants a serological response following vaccination was detected in 19/41 (46%) of the recipients of the RIT 4256 and in 19/40 (48%) of the RIT 4237 vaccine; none of the newborn infants had any reaction from either vaccine. It is concluded that the low passage strain RIT 4256 is not more immunogenic than the high passage vaccine RIT 4237 in humans. The vaccines do not differ in clinical reactogenicity for man.

Adult↗

Neonatal rotavirus vaccination with RIT 4237 bovine rotavirus vaccine: a preliminary report.

We vaccinated 244 newborn infants orally with RIT 4237 bovine rotavirus vaccine or placebo and followed them serologically and clinically for 16 months. Initially 39 of the 119 (33%) vaccine recipients compared with 1 of the 120 placebo recipients seroconverted by enzyme-linked immunosorbent assay-immunoglobulin M. After the first winter rotavirus season, at 7 months of age 55% of the vaccinated infants and 37% of the unvaccinated infants were rotavirus-seropositive by enzyme-linked immunosorbent assay-immunoglobulin G (P less than 0.01, chi square test). At 12 months of age, after a low rotavirus prevalence season, 34% of the vaccinated children and 23% of the unvaccinated children remained seropositive. There were 14 confirmed episodes of rotavirus gastroenteritis in the vaccine group and 10 episodes in the placebo group during the first 16 months. However, only 1 of the episodes in the vaccine group was severe, 4 were moderately severe and 9 were mild, whereas 7 episodes in the placebo group were severe and 3 were moderately severe (P less than 0.001 between groups, Fisher's exact test). There was no clear correlation between vaccine-induced clinical protection and initial serologic response (enzyme-linked immunosorbent assay-immunoglobulin M) to vaccination, but during follow-up severe rotavirus gastroenteritis was more likely to occur in children with no serum rotavirus immunoglobulin G antibody at the time of infection. We conclude at the present stage that neonatal rotavirus vaccination with RIT 4237 vaccine gives no protection against rotavirus infection but appears to modify the severity of gastroenteritis.

Clinical Trials as Topic↗

Immune response to rotavirus polypeptides after vaccination with heterologous rotavirus vaccines (RIT 4237, RRV-1).

The antibody response to individual rotavirus polypeptides after vaccination with live attenuated heterologous rotavirus vaccines was studied with a radioimmunoprecipitation assay (RIPA). Following vaccination with bovine rotavirus strain RIT 4237 and rhesus monkey rotavirus strain RRV-1, an antibody response was demonstrated mainly against the inner capsid polypeptides VP2 and VP6 and to a lesser extent against VP3/VP4. There was no qualitative difference between the vaccines in the antibody response; both vaccines induced antibodies against the same polypeptides. Quantitatively the antibody response to RRV-1 was somewhat stronger. All prevaccination sera contained by RIPA low levels of rotavirus antibodies. The effect of these antibodies on the 'take' of the vaccines is discussed.

Antibodies, Viral↗

A comparative trial of rapid oral and intravenous rehydration in acute diarrhoea.

37 children under the age of 5 years hospitalized for acute diarrhoea and dehydration were randomized to receive oral or intravenous rehydration during 6 to 12 hours. Rehydration was satisfactory in both groups, with correction of dehydration, metabolic acidosis and sodium deficit at equal rates. The reintroduction of normal feedings was successful in most of the orally rehydrated children after 12 hours, but often unsuccessful in the i.v. therapy group. Consequently the orally rehydrated children showed a 2.9% weight gain by the time of discharge whereas the intravenously treated children did not gain weight in the hospital. The duration of diarrhoea was also shorter in the orally rehydrated children. Thus oral rehydration therapy was equal or superior to even rapid intravenous rehydration therapy in the management of acute diarrhoea in children.

Acute Disease↗

Raised acute-phase glycoprotein and IgM levels in cord serum.

The usefulness of a combined screening for acute-phase glycoproteins and IgM level in cord sera to denote various intrauterine or delivery-associated disorders was tested in approximately 2,000 consecutive cord sera. Increased glycoprotein level, measured by sensitive and technically simple concanavalin A binding nephelometry, showed a significant association with birth injuries and abnormalities of amniotic fluid, whereas raised IgM levels were linked to maternal genitourinary infections and to cesarean sections performed because of fetal distress. The correlation between these putative risk indices was poor (r = 0.38). Both indices were connected with severe neonatal disease and/or poor outcome of the child, but since such conditions were also otherwise evident at birth, routine screening by these tests was considered unwarranted.

Acute-Phase Proteins↗

Spontaneous and inducible interleukin 1 production from peripheral blood monocytes in bacterial and viral infections in children.

Peripheral blood monocytes from children with severe bacterial infection showed a high level of spontaneous (unstimulated) production of interleukin 1 (IL-1). In viral respiratory or gastrointestinal infections there usually was little or no spontaneous IL-1 production from monocytes, and the values did not differ from those of children with no infections or inflammatory disease. Lipopolysaccharide-induced IL-1 production from monocytes was slightly but not significantly greater in bacterial infections than in viral infections and controls. Tuberculin (purified protein derivative)-induced IL-1 production from monocytes of patients with viral infections was significantly less than in bacterial infections and also slightly less than in controls. These results indicate that systemic bacterial infections activate spontaneous release of IL-1 from monocytes whereas uncomplicated viral infections usually do not. Tuberculin-inducible IL-1 activity of monocytes appears decreased in viral infections; this might be associated with suppressed cell-mediated immunity in such infections.

Bacterial Infections↗

A comparative trial of rhesus monkey (RRV-1) and bovine (RIT 4237) oral rotavirus vaccines in young children.

Heterologous live, oral rotavirus vaccines of rhesus monkey (RRV-1) and bovine (RIT 4237) origin were tested for immunogenicity, excretion of virus, and clinical reactions in six- to eight-month-old infants. Antibody response, indicating infection with the vaccine virus, was detected in 21 (88%) of 24 children receiving the RRV-1 vaccine and in 18 (75%) of 24 receiving the RIT 4237 vaccine. Excretion of virus in the stools within one week after vaccination was demonstrable in 84% of the RRV-1 and in 21% of the RIT 4237 vaccinees. RRV-1 vaccination was associated with a febrile response (over 38 C) that clustered on days 3 or 4 postvaccination in 64% of the recipient children. In addition, 20% of the RRV-1 vaccinees had watery stools on days 4 or 5. Fever on days 3 and 4 and loose stools were not seen in the RIT 4237 vaccinees. We concluded that in young children the RRV-1 (rhesus monkey) rotavirus vaccine is more immunogenic than the RIT 4237 (bovine) rotavirus vaccine, but vaccination with RRV-1 is associated with significant adverse reactions.

Administration, Oral↗

Oral rotavirus vaccination in breast- and bottle-fed infants aged 6 to 12 months.

Oral bovine rotavirus vaccine RIT 4237 was tested at two dose levels in 217 children between 6 and 12 months of age who received either breast milk or bottle milk (cow's milk or infant formula) before vaccination. Of the children 65% were initially seronegative for rotavirus ELISA IgG and IgM antibody. The full vaccine dose (10(8.3) 50% tissue culture infective doses, TCID50) induced seroconversion rates 81% and 86% and booster response rates 69% and 64% in breast and bottle-fed children, respectively. There was no difference in the vaccine response of infants receiving cow's milk or infant formula either. It is concluded that the RIT 4237 rotavirus vaccine at the dose level 10(8.3) TCID50 gives a satisfactory response in both breast- and bottle-fed children in this age group, but multiple vaccinations may be needed for maximal efficacy.

Administration, Oral↗

Glycine supplemented oral rehydration solutions for diarrhoea.

Two glycine supplemented oral rehydration solutions (ORS) and a standard ORS with sodium 60 mmol/l were compared for treatment of diarrhoeal dehydration in children. The solutions contained glycine 110 mmol/l and glucose 110 mmol/l (ORS60-Gly110), glycine 60 mmol/l and glucose 80 mmol/l (ORS60-Gly60), and glucose 144 mmol/l only (ORS60), respectively. The patients receiving ORS60-Gly110 had poor weight gain and increased stool and urine volumes after rehydration compared with the other two groups. The patients receiving ORS60-Gly60 had similar stool and urine volumes as those receiving standard ORS60. It is concluded that excess glycine in relation to sodium in an ORS may lead to osmotic diarrhoea, and a high amount of absorbed glycine may result in osmotic diuresis with poor net rehydration. Altogether, the present study failed to find any improvement ('Super-ORS') by addition of glycine to an ORS containing 60 mmol/l of sodium.

Child, Preschool↗

Effect of cholestyramine on acute diarrhoea in children receiving rapid oral rehydration and full feedings.

Cholestyramine 2 g twice daily for 3 days was compared to an equivalent placebo in a randomized double-blind study of infants hospitalized for acute diarrhoea. All the patients received oral rehydration with the WHO solution, and full feedings were reintroduced after 6-10 hours' rehydration. Cholestyramine therapy, initiated at the time of feedings, significantly shortened the duration of watery diarrhoea (0.8 +/- 0.6 vs. 2.3 +/- 1.6 days, p less than 0.005), although it did not significantly reduce the total stool volume. No adverse effects were associated with cholestyramine treatment. It is concluded that diarrhoea patients treated according to the present WHO guidelines may benefit from short adjunct therapy with cholestyramine.

Acute Disease↗

Kinetics of specific IgA, IgD, IgE, IgG, and IgM antibody responses in rubella.

Rubella-specific IgD and IgE antibodies were determined with a solid-phase enzyme immunoassay using enzyme-labeled heavy-chain specific anti-immuno-globulins, and the antibody responses in rubella infection were compared to IgM, IgA, and IgG antibodies. IgD and IgE antibodies increased rapidly after the onset of infection, remained at a high level for at least 2 months, and declined slightly by 6 months. In comparison, the IgM antibodies decreased more rapidly, whereas the IgG antibodies persisted longer at a steady level. By 6 months the mean levels of the different antibodies had declined from their maximal mean levels as follows: IgM, 52%; IgA, 42%; IgE, 35%; IgD, 29%; and IgG, 8%. Thus IgD and IgE antibodies, in spite of their known short half lives, persisted longer than IgM and IgA antibodies, which limits their diagnostic value. The IgA antibody responses were found too variable to substitute for IgM antibody determination in diagnosis of a recent rubella virus infection from a single serum specimen. Comparison of maternal and cord blood sera indicated that, in addition to IgG antibodies, rubella-specific IgD antibodies were found to cross the placenta.

Adult↗

Clinical efficacy of the RIT 4237 live attenuated bovine rotavirus vaccine in infants vaccinated before a rotavirus epidemic.

In a randomized, double-blind, placebo-controlled trial, 331 infants aged 6 to 12 months received orally, at an interval of 1 month, either two doses of live attenuated bovine rotavirus vaccine strain RIT 4237 or equivalent placebo. The vaccinations were carried out during September to November, a non-rotavirus season; only three cases of rotavirus diarrhea occurred in the study group before the vaccinations were completed. During the epidemic season from December to May, 31 patients with clinically significant rotavirus diarrhea required therapy. Five of these were among the 168 vaccine recipients, and 26 among the 160 placebo recipients (P less than 0.001), giving a vaccine protection rate of 82%. The incidence of clinically significant diarrhea from all causes was reduced by 76% in the vaccinees. As determined by an enzyme immunoassay antibody test with homologous virus antigen, seroconversion after vaccination was obtained in 53% of the initially seronegative infants. Clinical protection correlated well with seroconversion, but the vaccinees who failed to seroconvert also had less rotavirus diarrhea than the placebo recipients, suggesting that immunity may be mediated by factors other than serum EIA antibody. Seventeen of the 23 rotavirus isolates in the epidemic season that were typed were of serotype 1, two were of serotype 2, and four were of serotype 3. The protection rates against clinically significant diarrhea were 72%, 100%, and 100% for serotypes 1, 2, and 3, respectively. We conclude that epidemic infantile winter diarrhea associated with human rotaviruses can be significantly reduced by vaccination with the live attenuated RIT 4237 bovine rotavirus vaccine before the epidemic season.

Clinical Trials as Topic↗

Oral rehydration, rapid feeding, and cholestyramine for treatment of acute diarrhea.

Different combinations of fluid therapy, feeding regimen, and cholestyramine were compared in search for optimal treatment of infants hospitalized for acute diarrhea. The infants (n = 81) received either rapid oral rehydration using the oral rehydration solution-World Health Organization formula (sodium 90 mmol/L, ORS-WHO) or traditional oral fluid replacement using a commercial glucose-electrolyte solution (sodium 35 mmol/L). One-half of the infants in both groups received full feedings at 24 h of hospitalization; in the remaining infants, feedings were gradually introduced over a period of 5 days. In addition, all the children were randomized to receive either cholestyramine 2 g four times daily or an equivalent amount of placebo. Rehydration with ORS-WHO, but not traditional fluid replacement therapy, led to correction of initial metabolic acidosis after 6-10 h; no cases of hypernatremia were observed with the use of ORS-WHO. Rapid return to full feedings appropriate for age, including milk products, was associated with better weight gain and significantly shorter duration of diarrhea compared with gradual introduction of feedings. Cholestyramine treatment further shortened the duration of diarrhea without adverse effects in those children who had received ORS-WHO and thus were properly rehydrated. In contrast, in children with poor initial hydration, cholestyramine treatment was associated with prolonged metabolic acidosis. We conclude that treatment of acute diarrhea by rehydration with ORS-WHO and rapid introduction of full feedings is effective and safe, and this combination forms a therapy of choice for typical hospitalized cases of acute infantile diarrhea in Finland. Cholestyramine may be of value as an adjunct therapy after adequate rehydration.

Acute Disease↗

A comparative trial of cholestyramine and loperamide for acute diarrhoea in infants treated as outpatients.

Infants aged 4 to 36 months with acute diarrhoea (rotavirus 66%) were treated as outpatients with oral fluids and a rapid return to full feedings. In addition, the infants were randomized to receive for 3 days either cholestyramine 2 g twice daily (N = 10), an equivalent placebo 2 g twice daily (N = 15), or loperamide 0.10 mg/kg divided in three doses (N = 16). The duration of watery diarrhoea from the beginning of treatment was 0.9 +/- 1.0 days in the cholestyramine group, 2.5 +/- 1.3 days in the loperamide group, and 3.3 +/- 1.6 days in the placebo group (p less than 0.001 cholestyramine vs. placebo, p less than 0.005 cholestyramine vs. loperamide). The infants receiving cholestyramine also had a better weight gain than those receiving the placebo, and their metabolic acidosis was corrected sooner. There was no hyperchloraemia associated with the cholestyramine treatment. It is concluded that cholestyramine 2 g twice daily for 3 days can be safely used to shorten the course of acute diarrhoea. The use of loperamide in acute infantile diarrhoea does not appear justified.

Acute Disease↗