Explosive school-based measles outbreak: intense exposure may have resulted in high risk, even among revaccinees

Even high levels of measles vaccination coverage have not always prevented outbreaks of measles spread by airborne transmission. It has been suggested that a large inoculum might increase vaccine failure risk. Airbome transmission might occasionally entail a large measles inoculum. The epidemiologic relevance of measles among properly vaccinated persons (i.e., those vaccinated after 15 months of age and with live attenuated virus) is increased when they become contagious. The authors studied inoculum intensities as measured by proxy variables and the contagiousness of properly vaccinated persons who contracted measles among 51 measles patients infected in one school, at home, or elsewhere, utilizing preexisting records of measles cases and 214 healthy controls from an explosive school outbreak that occurred in a rural Finnish municipality in 1989. One "super-spreader" infected 22 others in one day, including eight once-vaccinated students and one twice-vaccinated student, probably during an assembly of 144 students in a poorly ventilated hallway with no sunlight. Those infected later at home had high measles risk, even if they were revaccinees. When siblings shared a bedroom with a measles case, a 78 percent risk (seven out of nine children) was observed among vaccinees. Vaccinees had approximately 2 days' shorter incubation time than unvaccinated persons. Vaccinated and unvaccinated students were equally able to infect their siblings. Total protection against measles might not be achievable, even among revaccinees, when children are confronted with intense exposure to measles virus.

Etiology of measles- and rubella-like illnesses in measles, mumps, and rubella-vaccinated children

The viral etiology of measles- or rubella-like illnesses after MMR (measles, mumps, and rubella) vaccination was studied prospectively in 993 acutely ill Finnish children with fever and rash in 1983-1995. Their sera were tested for adeno-, entero-, and parvovirus B19 antibodies. Sera of 300 children <4 years old were also tested for human herpesvirus 6 (HHV-6) antibodies. Measles and rubella had been excluded by previous antibody testing. Serologic diagnosis of adeno-, entero-, or parvovirus infection was based on EIA (IgM or IgG antibodies) and that of HHV-6 on indirect immunofluorescence. A viral etiology was verified in 368 cases, most commonly parvovirus (20%), followed by enterovirus (9%) and adenovirus (4%). Among young children, HHV-6 infection was found in 37 (12%). Thirty-eight children (4%) had double infections. This study confirms that measles- or rubella-like illnesses in MMR-vaccinated children are often caused by other viruses. Each suspected vaccine failure requires laboratory confirmation to maintain reliable surveillance and control and to establish the specific etiology of the disease.

Need for Haemophilus influenzae type b vaccination in Asia as evidenced by epidemiology of bacterial meningitis

OBJECTIVE

To evaluate the role of Haemophilus influenzae type b (Hib) infections in Asia by scrutinizing data on Hib meningitis.

DESIGN

A comprehensive literature search was performed in English and other languages. Special attention was paid to the age group of 0 to 4 years, in which the great majority of Hib meningitis occurs.

RESULTS

Twenty studies from as many countries indicated Hib to be a major pathogen in childhood meningitis. In series comprising nearly 2000 patients, Hib was responsible for at least 50% of cases in one-third of series and for at least 25% in three-fourths of series investigated and was the leading pathogen overall. The countries in South and Southeast Asia differed from the Middle East and East Asia in having a greater incidence of meningitis during the first 6 months of life; the proportions were 50 to 60% vs. 10 to 30%, respectively (P < 0.001).

CONCLUSIONS

Despite lacking data from many areas, belief in a paucity of Hib disease in Asia is not supported by the existing data; and because meningitis represents only 50 to 75% of all classical Hib manifestations and some cases occur after the age of 4 years, vaccination is warranted. The cumulative age curves suggest that conjugates with good immunogenic potential should be used, especially in South and Southeast Asia.

Haemophilus influenzae type b disease and vaccination in Europe: lessons learned

OBJECTIVE

To scrutinize the experiences of those European countries that have played a central role in understanding the behavior of and vaccination for Haemophilus influenzae type b (Hib) diseases, to enlighten weaknesses and to explore whether lessons learned would benefit other countries in combating Hib.

DESIGN

Epidemiologic and clinical data on Hib infections and vaccinations were analyzed, including all disease manifestations and all age groups. To improve reliability, sources that used active case finding were especially searched for.

RESULTS

In the prevaccination era meningitis represented 40 to 70% of all classical Hib diseases. Epiglottitis was the second most common presentation, except in southern Europe (data not available from former socialist countries). The overall incidence of meningitis and of all Hib disease combined for children ages 0 to 4 years was 23 and 41 per 100000, suggesting 9900 and 17800 cases per year, respectively. Including all age groups and entities, >20000 Hib cases occurred annually. Vaccination, accomplished with two or three primary doses and a late booster, has almost eliminated Hib disease in >10 countries, and >10000 cases per year are prevented. An age analysis of Hib meningitis suggests that strong early immunogenicity is not as imperative in Europe as in some other regions. The incidence of non-type b H. influenzae infections has not increased.

CONCLUSIONS

With Hib epidemiology comparable with that in Europe, good protection is achieved by various conjugate vaccines also with two primary doses only. However, active research on the whole Hib issue should be a priority, especially in southern and eastern European countries.

Etiology of pneumonia and other common childhood infections requiring hospitalization and parenteral antimicrobial therapy. SE-TU Study Group

The etiology of acute lower respiratory tract infections (mostly pneumonia) in children is well characterized, but these are only some of the community-acquired infections warranting parenteral antimicrobial therapy. We prospectively evaluated all such infections among children aged 3 months to 15 years by use of blood cultures, examination of nasopharyngeal aspirates, and serologies for 15 viral, 7 bacterial, and 1 protozoal agent. Immunocompromised patients and those with urinary tract infection, meningitis, or osteoarticular infection were excluded. In all, 170 children were included. The pathogenic agent was identified in 62% of the cases. Bacteria were detected in 54%, and a pneumococcus was found in 59% of the cases identified. Viruses were found in 15% overall. Sole bacterial or viral infections were detected in 47.1% and 8.1%, respectively. Since thorough screening established the etiology in less than two-thirds of patients ill enough to be hospitalized and treated parenterally, better diagnostics are needed, especially to identify those who would truly benefit from antimicrobial therapy.

Reduced incidence of septic arthritis in children by Haemophilus influenzae type-b vaccination. Implications for treatment

In many countries Haemophilus influenzae type b (Hib) is the second most common cause of septic arthritis in children. In Finland large-scale immunisation against Hib using conjugate vaccines began in 1986, four years after a multicentre prospective study of orthopaedic infections in children had started. Since 1982, including six years before and ten after starting routine Hib vaccination, there has been a major change in the pattern of septic arthritis. From 1982 to 1988, 32 of 61 cases (53%) were caused by staphylococci, 22 (36%) by Hib and 7 (11%) by other bacteria. Since 1988, Hib infection has disappeared, and one-third of cases of childhood septic arthritis has been eliminated. This change has allowed us to reduce initial antimicrobial therapy for such children to cover only Gram-positive cocci. The more limited treatment is safer, reduces cost, and simplifies treatment.

Reduced incidence of septic arthritis in children by Haemophilus influenzae type-b vaccination

In many countries Haemophilus influenzae type b (Hib) is the second most common cause of septic arthritis in children. In Finland large-scale immunisation against Hib using conjugate vaccines began in 1986, four years after a multicentre prospective study of orthopaedic infections in children had started.

Since 1982, including six years before and ten after starting routine Hib vaccination, there has been a major change in the pattern of septic arthritis. From 1982 to 1988, 32 of 61 cases (53%) were caused by staphylococci, 22 (36%) by Hib and 7 (11%) by other bacteria. Since 1988, Hib infection has disappeared, and one-third of cases of childhood septic arthritis has been eliminated. This change has allowed us to reduce initial antimicrobial therapy for such children to cover only Gram-positive cocci. The more limited treatment is safer, reduces cost, and simplifies treatment.

Total elimination of measles in Finland

On average, 15,000 cases of measles occurred annually in Finland before the initiation of a vaccination programme in 1975. Because of insufficient activity, the vaccination coverage failed to reach the required level of over 90%, and cases continued to occur. The policy was revolutionized in 1982 by launching a project in which the Schwarz strain was substituted by an attenuated Enders-Edmonston strain given as a component of a trivalent live-virus measles-mumps-rubella vaccine (MMRII). This vaccine is given twice, at the ages of 14-18 months and 6 years. The impact of the vaccinations has been monitored in several prospective studies. In addition to a very favourable safety profile, good immunogenicity and excellent clinical effectiveness have also been demonstrated. Since 1996 not a single case of measles has been found in Finland, although cases have been searched actively and serological confirmation has been required. Total interruption of virus circulation has brought a new problem: the possibility of vaccinees to acquire natural boosters is so rare that waning immunity has become a reality. As there is a continuous risk of measles originating from a foreign source, the only tool against an outbreak is to maintain a high vaccination coverage and to continue the two-dose schedule as a minimum policy.

Single-dose and steady-state pharmacokinetics of a new oral suspension of ciprofloxacin in children

OBJECTIVE

Quinolones are used ever increasingly in pediatrics, although officially they are still contraindicated. Lack of evidence of arthropathic effects in human offspring favors their use, but little is known about the pharmacokinetics of oral or parenteral ciprofloxacin in children, especially those without cystic fibrosis.

DESIGN

We studied 16 non-cystic fibrosis patients ranging in age from 0.3 to 7.1 years to whom the new suspension formulation of ciprofloxacin (10 mg/kg body weight) was given orally three times daily. Single-dose and steady-state pharmacokinetic parameters were elucidated.

RESULTS

Ciprofloxacin was rapidly absorbed. The maximum plasma concentrations, with the means varying from 1.7 to 3.6 mg/L, were reached within 1 hour, almost regardless of whether single-dose administration or steady state. The mean oral clearance was lower in children <6 years of age than in those >/=6 years. Terminal half-life values, with the means varying only between 4.2 and 5.1, suggest that dosing recommendations based on body weight are pertinent, although caution should be exercised in small infants. No arthropathic or other adverse events attributable to ciprofloxacin suspension were observed.

CONCLUSION

A dose of the suspension form of ciprofloxacin of 10 mg/kg body weight given orally three times daily seems appropriate in children, provided the drug is clearly indicated.

Physicians' opinions about the management of hypertension: changes in Finland between 1985 and 1992

The successful management of hypertension requires an active involvement of physicians. We studied trends in Finnish physicians' opinions about the management of hypertension between 1985 and 1992. The response rates in these two random samples of physicians were 68% and 56%, respectively. Physicians who reported regularly treating hypertensive patients were included in our analyses (n1 = 319, n2 = 470). Fifty per cent of physicians used diastolic blood pressure of 100 mm Hg as a criterion for starting drug treatment and a goal blood pressure of 90 mm Hg was reported by 60% of physicians. Both levels decreased from 1985 to 1992. The variation in both of these blood pressure levels as reported by the physicians were wide both in 1985 and 1992. The activity in promoting non-pharmacological measures such as exercise and restriction of fat intake improved during this time period. The choice of drugs for anti-hypertensive therapy changed drastically from 1985 to 1992. For younger patients ACE inhibitors became the drug of choice and for older patients Ca-blockers gained popularity from diuretics. A similar shift can also be seen in the sales statistics. Whether this increased activity in starting drug therapy and using new drugs will improve the outcome of treatment remains to be seen.

Meningococcal vaccines. Current status and future possibilities

Meningococcal disease causes great emotion and anxiety in the families and caregivers of patients. Numbers of such patients are usually small in industrialised countries, unlike those in many regions--especially in subsahelian Africa. Vaccines have been tried for more than 80 years; at present there are available polysaccharide vaccines against groups A, C, Y and W135, and a protein-based vaccine against group B. A property common to all is their relative efficacy (75 to 100%) at school age and after, and an acceptably short persistence of antibodies. Small children pose the major challenge, in whom there is essentially evidence of clinical protection only against group A and C diseases. With vaccines against other serogroups protection is possible, but not yet proven in controlled clinical studies. The search is on for help from various modifications, including the conjugation technique, to transform the independent nature of polysaccharide response towards T cell dependence, as was done earlier in Haemophilus influenzae type b vaccines. First trials along this path are encouraging although, again, group B meningococci pose special problems. The next few years will probably see a new generation of meningococcal vaccines. Generally speaking, the incidence of meningococcal disease is too low to indicate vaccinations for the whole population, or even children, but some risk groups and epidemics are important exceptions. To date, bivalent group A + C or tetravalent group A + C + Y + W135 polysaccharides, or an outer membrane protein-based group B vaccine, are the products to be used when the indications, that may vary from country to country, are considered met. A strong herd immunity effect, demonstrated with group A and C vaccinations, facilitates extinction of an epidemic since large-scale vaccinations can be restricted only in the major risk groups, children and in various schools. Prompt intervention demands, however, a functioning mechanism which detects very early on a pending epidemic. Unfortunately, such a mechanism is often lacking in countries often hit by this deadly disease.

Haemophilus influenzae type b disease and vaccination in Latin America and the Caribbean

OBJECTIVE

Conjugate vaccines are highly effective in preventing Haemophilus influenzae type b (Hib) diseases. Data on the epidemiology of Hib disease in Latin America and the Caribbean are not easily accessible, are incomplete and are deserving of critical analysis.

METHODS

Relevant information in Spanish, English and Portuguese from over 20 regions in 16 countries was reviewed, with special attention to all Hib diseases and to children < 5 years because of their proneness to disease. Total number of cases and deaths were estimated from the incidence rates obtained from 10 studies.

RESULTS

Taking into account variation between among countries, the overall incidence of Hib meningitis at age 0 to 4 years was estimated as 35 per 100,000, which would imply 20,000 cases annually in the region. An estimated rate of 60 per 100,000 for all Hib disease suggests 33,000 cases per annum. In all age groups at least 40,000 annual cases and 5000 deaths occurred annually. Given that the true role of Hib pneumonia is unknown because of data are much lacking for nonbacteremic cases, these figures are probably underestimations. Because large scale vaccination programs are being implemented in only 3 countries, the impact on Hib epidemiology has been minimal.

CONCLUSIONS

Hib diseases are common in Latin America and the Caribbean, and use of conjugate vaccines is minor. Concurrently with better epidemiologic studies, their use should be extended, preferably in combination with other vaccines. Making Hib diseases notifiable would be one step for better recognition of their importance.

Simplified treatment of acute staphylococcal osteomyelitis of childhood. The Finnish Study Group

OBJECTIVE

Recommendations on treatment of acute staphylococcal osteomyelitis of children, based mostly on retrospective analyses, comprise surgical drainage, up to 6 weeks fo antimicrobials guided by the erythrocyte sedimentation rate, and the possibility of switching to the oral route only if monitoring of serum bactericidal titer is guaranteed. A prospective study was conducted to test whether the treatment could be simplified.

DESIGN

Fifty pediatric cases of acute Staphylococcus aureus osteomyelitis were randomized to receive 150 mg/kg/day of cephradine divided in four doses, or 40 mg/kg/day in four doses of clindamycin. The treatment was initiated intravenously, but switched to oral administration mostly within 4 days, using the same doses. The peak antimicrobial serum inhibitory titer or bactericidal titer was not measured. The course of illness was monitored by blood leukocytes, erythrocyte sedimentation rate, and serum C-reactive protein. The follow-up was extended to 1 year posthospitalization.

SETTING

Eight tertiary pediatric-orthopedic hospitals in Finland.

MAIN OUTCOME MEASURE

Full recovery and remaining healthy at least 12 months from hospital discharge.

RESULTS

The lower and upper extremities were affected in 72% and 8% of patients, respectively. No surgery at all or needle aspiration only was performed in 62% and drilling in 38%. C-reactive protein and the sedimentation rate normalized within 9 days and 29 days, respectively. X-ray changes developed in 68% but had no prognostic significance. The mean hospitalization time was 11 days, and the total duration of antimicrobials was 23 days. No failure has occurred nor have long-term sequelae been observed in any patient.

CONCLUSIONS

Treatment of pediatric acute staphylococcal osteomyelitis can be simplified and costs reduced by keeping surgery at a minimum, shortening hospitalization and the course of antimicrobials, switching quickly to the oral route, and not monitoring serum bactericidal activity.

Neonatal Candida parapsilosis outbreak with a high case fatality rate

A Candida parapsilosis outbreak of 58 cases in a neonatal intensive care unit lasted for 55 months. Patients infected by or colonized with C. parapsilosis were mainly very low birth weight infants (birth weight < 1500 g). Their mean birth weight was 817 g and their mean gestational age was 28 weeks. Statistical analysis including logistic regression confirmed that prematurity was the main risk factor. The analysis also suggested that C. parapsilosis infection (or colonization) was associated with a poor prognosis. In infants with gestational age < 29 weeks the risk for death in C. parapsilosis-infected patients was 16-fold greater than in those with no C. parapsilosis infection. The case fatality rate of C. parapsilosis patients was higher than that of the controls (9 of 23 vs. 1 of 40; P < 0.0001). The outbreak was most likely a result of cross-infection because C. parapsilosis could be isolated only from the patients and from the hands of four nurses immediately after they had cared for a colonized patient. Cessation of the outbreak was temporally associated with long term parenteral fluconazole (6 mg/kg/day) prophylaxis.

Neonatal immunization: response to Haemophilus influenzae type b-tetanus toxoid conjugate vaccine

OBJECTIVE

To study the immunogenicity and tolerability of Haemophilus influenzae type b (Hib) conjugate vaccine administered in the neonatal period.

DESIGN

Hib capsular polysaccharide (PS)-tetanus toxoid conjugate vaccine (PRP-T) was given to 120 neonates at 2 days of age, followed by PRP-T or the Hib PS vaccine at 4 months and a PRP-T booster at 14 months. Their anti-Hib PS concentrations were compared with those in children receiving PRP-T at 2 and 4 months or at 4 months.

RESULTS

No serious adverse reactions were noted. The geometric mean concentration of anti-Hib PS at the age of 2 days was 0.34 micrograms/mL and at 4 months was 0.12 micrograms/mL. This was significantly more than the concentration in unimmunized infants at this age and 3.5 times more than expected, taking into account the natural decay of transplacentally acquired antibodies. Such a response was not seen in infants with a high (greater than 3.0 micrograms/mL) neonatal antibody concentration. The PRP-T vaccine given at 4 months elicited an antibody response in all infants and Hib PS in 62%, indicating immunologic priming. At 14 months, a higher percentage of the infants who had received PRP-T at 2 days and 4 months than of those who had received PRP-T at 4 months only had anti-Hib PS concentrations greater than 0.15 micrograms/mL. All infants responded well to the booster at 14 months. There was no evidence of immunologic tolerance.

CONCLUSIONS

Neonatal immunization with PRP-T was safe and well tolerated in Finnish infants, and it would be worthwhile to further study its effects in higher risk populations.

Risk Behavior for Travelers' Diarrhea Among Finnish Travelers

Background: Contaminated food and drink are the primary sources of traveler's diarrhea (TD). Identification of the characteristics that make a traveler more prone to TD is needed to improve prevention and therapy of this illness. Methods: We evaluated, by questionnaire, the association of dietary errors with TD among 933 adult Finnish tourists vacationing in Morocco. A stool specimen was obtained from patients in the group that developed TD at the onset of the diarrheal episode, and from all participants in the study on their return to Finland. Results: Only 5% of the 933 subjects who responded to the questionnaire, and who gave a stool sample, had adhered strictly to generally accepted recommendations. About 45% made five or more dietary errors during the trip; of these, 75% consumed raw vegetables, 65% salads, 33% puddings, 32% mayonnaise or other cold dressings, 31% consumed food bought from street vendors, 29% consumed cold meat, 18% cold sandwiches, 4% drank tap water, and 2% consumed raw meat. The age of the subjects did not correlate with the number of dietary errors. Subjects who had been abroad during the preceding 12 months committed more dietary errors than those who had not (mean 3.9 versus 4.5; p <.001). Also, subjects who spent 2 weeks in Morocco committed more dietary errors than those who spent only 1 week (mean 4.0 versus 4.8; p <.001). However, no association between TD and the number of dietary errors was observed. Differences with respect to eating habits were not observed between subjects, with or without TD or with or without an identified pathogen in stool specimens. There was no correlation between eating habits and the presence, or absence, of a specific pathogen in the stool sample; this is with the exception of Campylobacter spp: subjects with this pathogen consumed steak tartar or salad more often than did other subjects. Conclusions: Etiologic agents are so ubiquitous in this high-risk area that instructions to avoid certain foodstuffs commonly thought to be contaminated may be to some extent without value. Moreover, dietary self restraint proved to be impossible in the real situation. (J Travel Med 2:77-84, 1995)

Oral glycerol and intravenous dexamethasone in preventing neurologic and audiologic sequelae of childhood bacterial meningitis. The Finnish Study Group

To assess the value of adjunctive intravenous dexamethasone (DXM) and oral glycerol (GLY) for the treatment of bacteriologically proved bacterial meningitis, 122 infants and children with bacterial meningitis were randomly assigned to receive DXM intravenously (n = 32), GLY orally (n = 30), DXM plus GLY (n = 34) or neither (n = 26) of these drugs. All patients were treated with the same antimicrobial agent, ceftriaxone. The patients were followed neurologically for as long as 6 months. A thorough hearing evaluation was performed routinely 2 months or more after discharge from hospital. Overall 4 (7%) of the GLY-treated patients, compared with 11 (19%) of those not given GLY, developed audiologic or neurologic sequelae (P = 0.052), the relative risk of sequelae being 2.94 (95% confidence interval, 0.99 to 8.72). The patients who had received GLY showed less severe or profound bilateral hearing impairment than those not given GLY (0 vs. 7%, P = 0.049), and none of them had other neurologic abnormalities 3 or 6 months after discharge, compared with 5 (9%) of those not treated with GLY (P = 0.024). The DXM recipients showed only a tendency to less severe hearing impairment than those not given DXM. In conclusion oral GLY prevented neurologic sequelae in infants and children with bacterial meningitis more effectively than intravenous DXM.

The elimination of indigenous measles, mumps, and rubella from Finland by a 12-year, two-dose vaccination program

BACKGROUND

In the 1970s measles, mumps, and rubella were rampant in Finland, and rates of immunization were inadequate. In 1982 a comprehensive national vaccination program began in which two doses of a combined live-virus vaccine were used.

METHODS

Public health nurses at 1036 child health centers administered the vaccine to children at 14 to 18 months of age and again at 6 years, and also to selected groups of older children and young adults. Vaccination was voluntary and free of charge. In follow-up studies, we focused on rates of vaccination, reasons for noncompliance, adverse reactions, immunogenicity, persistence of antibody, and incidence of the three diseases. Since 1987, paired serum samples have been collected from all patients with suspected cases of measles, mumps, or rubella.

RESULTS

Over a period of 12 years, 1.5 million of the 5 million people in Finland were vaccinated. Coverage now exceeds 95 percent. The vaccine was efficient and safe, even in those with a history of severe allergy. No deaths or persistent sequelae were attributable to vaccination. The most frequent complication requiring hospitalization was acute thrombocytopenic purpura, which occurred at a rate of 3.3 per 100,000 vaccinated persons. The 99 percent decrease in the incidence of the three diseases was accompanied by an increasing rate of false positive clinical diagnoses. In 655 vaccinated patients with clinically diagnosed disease, serologic studies confirmed the presence of measles in only 0.8 percent, mumps in 2.0 percent, and rubella in 1.2 percent. The few localized outbreaks were confined to patients in the partially vaccinated age groups. There are now fewer than 30 sporadic cases of each of the three diseases per year, and those are probably imported.

CONCLUSIONS

Over a 12-year period, an immunization program using two doses of combined live-virus vaccine has eliminated indigenous measles, mumps, and rubella from Finland. Serologic studies show that most reported sporadic cases are now due to other causes, but a continued high rate of vaccination coverage is essential to prevent outbreaks resulting from exposure to imported disease.

The effect of a recent previous visit to a physician on outcome after childhood bacterial meningitis

OBJECTIVE

To assess the effect of a recent previous visit to a physician on the outcome of meningitis in children.

DESIGN

Evaluation of data from children examined by a physician and sent home, either the previous day or 2 to 4 days before meningitis was diagnosed, and children whose meningitis was diagnosed at once. The patients were examined daily during hospitalization, neurologic examinations were repeated at 2 weeks and 3 and 6 months after discharge, and hearing was assessed 2 or more months after discharge.

SETTING

Eighteen pediatric hospitals in Finland from 1984 through 1991.

POPULATION

A total of 325 children aged 3 months to 15 years with bacterial meningitis.

MAIN OUTCOME MEASURES

Clinical and laboratory findings on admission, recovery during hospitalization, mortality, and neurologic abnormalities at 6 months of follow-up.

RESULTS

In 74% of the patients, meningitis was diagnosed at once, 14% had visited a physician on the previous day, and 11% had seen a physician 2 to 4 days before diagnosis. The group seen 2 to 4 days earlier had a better level of consciousness, less frequent seizures, and more respiratory symptoms and otitis media than the other groups. The cerebrospinal fluid leukocyte count, white blood cell count, and erythrocyte sedimentation rate were highest and the cerebrospinal fluid glucose concentration was lowest in the children who had visited a physician 2 to 4 days earlier, although they also had lower cerebrospinal fluid protein and urine sodium and potassium levels. This group had the most rapid return to normal consciousness. There was no difference in the incidence of hearing impairment or neurologic sequelae. Even the mortality was virtually the same in the three groups: 4%, 4%, and 3% in the "same day," "previous day," and "2 to 4 days earlier" groups, respectively.

CONCLUSIONS

Children who had visited a physician the previous day or 2 to 4 days before meningitis was diagnosed did not exhibit an increased frequency of hearing impairment, other neurologic abnormalities, or overall adverse outcome compared with children whose meningitis was diagnosed at once.

Clinical comparison of the Haemophilus influenzae type B polysaccharide-diphtheria toxoid and the oligosaccharide-CRM197 protein vaccines in infancy

OBJECTIVE

To compare two Haemophilus influenzae type B (HiB) conjugate vaccines, a polysaccharide-diphtheria toxoid conjugate (PRP-D) vaccine and an oligosaccharide-CRM197 protein conjugate (HBOC [PRP-CRM]) vaccine, in the same population.

DESIGN

One hundred twenty-five thousand infants were randomized to receive the PRP-D or HBOC vaccine. Primary immunization consisted of two doses of either vaccine administered at 4 and 6 months and a booster dose was given at 14 to 18 months. Protection was assessed by recording episodes of invasive disease with HiB isolated from the blood or another normally sterile body site.

SETTING

One thousand thirty-six child health care centers in Finland.

PARTICIPANTS

Infants born in Finland during the 24-month period from 1987 to 1989.

INTERVENTION

Each vaccine dose was injected intramuscularly in a volume of 0.5 mL. At the same time, a separate site was injected with the diphtheria and tetanus toxoids and pertussis vaccine at 4 months of age, with inactivated poliovirus vaccine at 6 months of age, and with measles-mumps-rubella vaccine at 14 to 18 months of age.

MAIN RESULTS

The mean anticapsular antibody concentration 1 month after the second dose was 0.63 micrograms/mL and 4.32 micrograms/mL in the PRP-D and HBOC vaccine recipients, respectively. The booster dose resulted in a high antibody concentration: 33.3 micrograms/mL and 58.3 micrograms/mL for PRP-D and HBOC vaccine recipients, respectively. At 36 months of age, the antibody concentration declined to 2.5 micrograms/mL and 5.6 micrograms/mL for PRP-D and HBOC vaccine recipients, respectively. After two doses of the vaccine, there were five episodes (39 were expected based on historical controls) of invasive HiB disease in the PRP-D group and two episodes (35 were expected) in the HBOC group. Hence, an 87% (95% confidence limit [CL], 69, 96) protection rate in the PRP-D group and a 95% (95% CL, 76, 99) protection rate in the HBOC group were achieved. No episodes occurred after the booster dose in either group.

CONCLUSIONS

Both the PRP-D and HBOC vaccines are safe and effective. A two-dose primary vaccination schedule seems appropriate, at least in circumstances prevailing in Finland and probably in other areas with similar epidemiological effects of HiB disease.

Disappearance of epiglottitis during large-scale vaccination with Haemophilus influenzae type B conjugate vaccine among children in Finland

Surveillance of blood-culture-proven epiglottitis was conducted in Finland from 1985 through 1992. Among children (< 16 years), all bacteria causing epiglottitis, and among adults, Haemophilus influenzae were included. H influenzae type b (Hib) caused 226 (97%) of cases among children. Among adults with H influenzae epiglottitis (total of 20), 19 were caused by Hib. In 1986, vaccine trials with Hib-conjugate vaccines started in Finland, with vaccination coverage of 94% to 98% of infants. Vaccinations did not yet have an effect on the occurrence of epiglottitis in 1985 or 1986 when the annual incidence among children was 5.3/100,000, among those less than 5 years of age was 13.2/100,000, and among adults was 0.08/100,000. In 1987 through 1992 the proportion of vaccinated children increased steadily while the incidence of Hib epiglottitis decreased from 50 to 60 cases seen annually in 1985 and 1986 to 2 cases in 1992. There was no increase in the occurrence of epiglottitis caused by other pathogens. In conclusion, there is now a safe and efficient way to prevent the majority of epiglottitis cases among children with the new Hib-conjugate vaccines.

The usefulness of C-reactive protein levels in the identification of concurrent septic arthritis in children who have acute hematogenous osteomyelitis. A comparison with the usefulness of the erythrocyte sedimentation rate and the white blood-cell count

Thirty-six children who had bacteriologically confirmed acute hematogenous osteomyelitis but did not have concurrent septic arthritis, and ten children who had confirmed acute hematogenous osteomyelitis and concurrent septic arthritis, were followed for one year to compare the changes in the C-reactive protein level in the blood, the erythrocyte sedimentation rate, and the white blood-cell count. In both groups, the mean C-reactive-protein values were high (eighty-four milligrams per liter in the children who had septic arthritis and osteomyelitis and sixty-five milligrams per liter in those who had osteomyelitis only) at the time of admission to the hospital. However, in the group that had septic arthritis, the increase was significantly higher (p < 0.01) as early as the second day and a normal level (less than twenty milligrams per liter) was reached significantly later (p < 0.001) than in the group that had osteomyelitis only (11 +/- 7 days compared with 6 +/- 3 days [mean and standard deviation]). The erythrocyte sedimentation rate showed the same tendency, but the difference in the rates between the groups did not become evident until the fifth to fourteenth days after admission. A normal erythrocyte sedimentation rate (less than twenty millimeters per hour) was reached in 25 +/- 12 days in the children who had septic arthritis and in 17 +/- 10 days in those who did not (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Serum C-reactive protein, erythrocyte sedimentation rate, and white blood cell count in acute hematogenous osteomyelitis of children

OBJECTIVE

The aim of this prospective study was to compare the clinical value of the erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and white blood cell (WBC) count in diagnosis and follow-up of acute hematogenous osteomyelitis in children.

DESIGN

Forty-four children aged 2 weeks to 14 years with bacteriologically confirmed acute hematogenous osteomyelitis were examined. Staphylococcus aureus was responsible in 39 cases (89%), Haemophilus influenzae type b in 3 cases (7%), pneumococcus in 1 case (2%), and a microaerophilic streptococcus in 1 case (2%). ESR was measured at the time of admission and on days 3, 5, 7, 10, 14, 19, and 29 of treatment, and CRP was measured on the same days as ESR but also on days 2, 9, 12, 17, and 23. WBC count was examined at the time of admission and on days 5, 10, 19, and 29.

RESULTS

ESR was elevated (> or = 20 mm/h) initially in 92% of the cases; the mean value was 45 mm/h, and the peak values (mean 58 mm/h) were reached on days 3 to 5. After this the levels slowly returned to normal in approximately 3 weeks (mean 18 days). CRP was elevated (> 19 mg/L) at the time of admission in 98% of the cases, the mean value being 71 mg/L. The peak CRP value was reached on day 2 (mean 83 mg/L). The decrease was very rapid, normal values being reached within a week (mean 6.9 days). The WBC count was a poor indicator of acute hematogenous osteomyelitis, since only 35% of the children had leukocytosis (WBCs > 12 x 10(9)/L) at the time of admission.

CONCLUSIONS

In patients with acute hematogenous osteomyelitis, CRP increased and especially decreased significantly faster than ESR, reflecting the effectiveness of the therapy given and predicting recovery more sensitively than ESR or WBC count.

Risk of infection with Mycobacterium tuberculosis among children and mothers in Somalia

The prevalence of infection with Mycobacterium tuberculosis in prewar Somalia was surveyed by testing the tuberculin sensitivity of 2,792 infants and children and 446 mothers in two towns: Burao in the dry north and Kismayo in the humid south. Sensitivity increased with age, but considerable differences prevailed between the towns. In Burao a roughly linear increase in sensitivity was found, with no sensitivity in infancy, sensitivity in 19% of children at 7 years, and sensitivity in 54% of children at 15 years; in Kismayo the corresponding figures were 9%, 28%, and 47%, respectively. Together, the correlation of prior BCG vaccination with a positive tuberculin test in Burao and the lack of these findings in Kismayo suggested that vaccination had partly failed in Kismayo, where living conditions also favored the transmission of M. tuberculosis. The annual risk of M. tuberculosis infection was approximately 1% higher in the south than in the north and was much higher during the first 3 years of life than later. This study--the first defining the risk of M. tuberculosis infection among children of various ages in Somalia--indicates that this risk is greatest in the southern parts of the country and among infants and young children.

Acute haematogenous osteomyelitis in children in Finland. Finnish Study Group

The purpose of the study was to evaluate the history, clinical picture and diagnostic difficulties of acute haematogenous osteomyelitis (AHOM) in children. Forty-seven children under the age of 15 with bacteriologically proven AHOM were collected prospectively in Finland in 1981-93. Staphylococcus aureus was responsible for 89% of the cases. The commonest sites affected were the tibia (25%) and the femur (23%) followed by the pelvis (15%) and the calcaneus (11%). Sites other than the long bones increased in frequency in children over the age of 4 years. Most of the children came with a history of a week or less with classic signs and symptoms of AHOM, increased C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) values but negative X-rays. Delay in hospital admission was observed in 19%. In 11% antimicrobial therapy was not instituted within 48 hours on ward. All children were clinically healthy at the 1-year check-up with minor X-ray changes seen in 11 patients. We conclude that children in Finland seek treatment early in the course of AHOM and have a good outcome. S. aureus is the main aetiological agent affecting primarily the long bones, but in older children pelvic and calcaneic sites are also frequent. No significant delays affecting the outcome were noticed in admittance to hospital or in the diagnosis of AHOM.

Short-term treatment of traveler's diarrhea with norfloxacin: a double-blind, placebo-controlled study during two seasons

Clinical efficacy of norfloxacin for treatment of traveler's diarrhea in 106 Finnish tourists vacationing in Morocco was evaluated during two different seasons. When the criteria for diagnosis of traveler's diarrhea were fulfilled, norfloxacin (400 mg) or a placebo was given orally, twice daily for 3 days. All symptoms and signs subsided sooner in the norfloxacin group. The clearest difference was observed in the duration of diarrhea: 1.2 days in the norfloxacin group vs. 3.3 days in the placebo group (P < .001). The duration of diarrhea due to particular species was as follows for the two groups: in cases due to Salmonella enterica, 1.1 vs 4.1 days (P < .01); in cases due to Campylobacter jejuni, 1.8 vs. 5.0 days (P < .01); and in cases due to enterotoxigenic Escherichia coli, 1.0 day vs. 3.1 days (P < .01). The rate of full recovery during administration of norfloxacin or a placebo was also greater among the norfloxacin recipients: 84% vs. 47% (P < .001). No significant adverse effects were reported. Norfloxacin proved to be safe and effective in therapy for traveler's diarrhea.

Acute thrombocytopenic purpura following measles, mumps and rubella vaccination. A report on 23 patients

An acute thrombocytopenic purpura developed shortly after measles-mumps-rubella vaccination in 23 of approximately 700,000 children immunized over a period of seven years. The mean interval from inoculation to the onset of purpura was 19 days. Bone marrow aspirates obtained from 13 patients showed increased or normal amounts of megakaryocytes. Platelet survival time was markedly shortened in the two patients studied. Fifteen patients recovered (the platelet count exceeded 100 x 10(9)/l) in one month, five in two months and two in six months. Increase in platelet-associated immunoglobulin was detected in 10 of 15 patients. Circulating antiplatelet autoantibodies (AAb) against glycoprotein IIb/IIIa were detected in 5 of 15 patients. The findings are compatible with an autoimmune mechanism triggered by immune response to measles-mumps-rubella vaccination. As evaluated by the clinical course and the presence of AAb, post-vaccination thrombocytopenic purpura appears to be indistinguishable from childhood acute idiopathic thrombocytopenic purpura.

Length of prediagnostic history related to the course and sequelae of childhood bacterial meningitis

The relationship between length of prediagnostic history and course and sequelae of childhood bacterial meningitis was prospectively examined by collecting data from 286 children with bacteriologically confirmed bacterial meningitis. The cases were divided into three groups: short (< or = 24 hours, N = 141); intermediate (> 24 to 48 hours, N = 75); and long (> 48 hours, N = 70) history. The level of consciousness and serum C-reactive protein normalized sooner during hospitalization in patients with a longer history. They also showed neck stiffness more often and longer and had thrombocytosis earlier and more prominently than patients with a shorter history. The differences were not influenced by etiology, sex or age. The occurrence of neurologic abnormalities in the hospital or during the first 6 months after discharge was not affected by duration of illness before hospitalization. We conclude that our results support the view that bacterial meningitis presents in two forms. At presentation the more acute form often has a history of less than 24 hours and poses a great danger to the patient. In contrast the other form develops insidiously and is more difficult to detect but does not have a worse prognosis than the acute form.

Rapid disappearance of Haemophilus influenzae type b meningitis after routine childhood immunisation with conjugate vaccines

Mortality from meningitis caused by Haemophilus influenzae type b (Hib), a disease that affects mainly infants and young children, can reach 5% in industrialised countries and ten times that in non-industrialised countries. To determine the efficacy of vaccination against Hib, we carried out a retrospective survey of the incidence of Hib meningitis over five decades in the Greater Helsinki area of Finland, where all children with bacterial meningitis are treated in one of three centres. Except for a meningococcal epidemic in the early 1970s, Hib was the leading cause of childhood bacterial meningitis until the Hib conjugate vaccines changed the picture profoundly. In 1986-87 the polysaccharide-diphtheria toxoid conjugate (PRP-D) was given experimentally to 50% of infants. In 1988-89 all infants were vaccinated, 50% with PRP-D, 50% with another conjugate vaccine, the oligosaccharide-CRM197 protein conjugate (HbOC). Since 1990 a third conjugate vaccine, the polysaccharide-tetanus toxoid (PRP-T), has been administered routinely to all infants. The vaccines were administered at age 3-6 months, with a booster dose at 14-18 months. In the first 5 years of the Hib vaccination programme the number of cases of Hib meningitis in children aged 0-4 years fell sharply, from 30 in 1986 (the first year of the programme) to none in 1991. The decline contrasts sharply with the rising trend up to the mid 1980s. Vaccination seems to be the only explanation for the observed change in the epidemiology of Hib meningitis.

C-reactive protein in measles

Seventy-two children with early measles (1st-3rd day of rash), presenting at two centres in Santiago, Chile, were classified as having mild ('ordinary measles', n = 50), or moderate to severe measles ('primarily severe measles', n = 22). The level of serum C-reactive protein (CRP) was determined by nephelometry from a finger prick sample. The mean CRP value in ordinary measles, 19 mg/l, was significantly lower (P less than 0.001) than in primarily severe measles where the mean CRP was 65 mg/l. During late measles (5th-8th day of rash), the mean CRP was 19 mg/l if the child recovered uneventfully (n = 35), whereas the mean level of 123 mg/l (P less than 0.001) was encountered when the child suffered from complicating pneumonia (n = 22). We conclude that the simple quantitative CRP determination is a useful alarm signal during the course of measles: elevated levels point to severity or complications in recovery.

Thrombocytosis and thrombocytopenia in childhood bacterial meningitis

To assess factors affecting the development of reactive thrombocytosis during bacterial meningitis, thrombocyte counts of 311 children with cerebrospinal fluid culture-positive bacterial meningitis were followed during hospitalization. Thrombocytosis (platelet counts greater than 500 x 10(9)/liter) was seen in 49% of the patients after the first week of treatment. Thrombocyte counts were higher in infants and in patients with long duration of illness before admission. Subdural effusion and cephalosporin therapy were associated with more pronounced thrombocytosis We found no relation between thrombocytosis and neurologic complications, but the patients who died developed thrombocytopenia instead of thrombocytosis. The difference between the thrombocyte curves of the surviving and dying patients might be utilized in predicting the final outcome in the severest cases of bacterial meningitis. We speculate that inflammatory cytokines, especially interleukin 1-beta, induce reactive thrombocytosis in bacterial meningitis.

Finnish efficacy trials with Haemophilus influenzae type b vaccines

The first Finnish trial with Haemophilus influenzae type b vaccine was conducted during 1973-1974. It demonstrated that the polysaccharide vaccine was 90% efficacious in children greater than or equal to 18-24 months old. The immunologically superior polysaccharide-protein conjugate vaccines have been used since 1986 in randomized trials. The PRP-D vaccine (polysaccharide conjugated to diphtheria toxoid) was 90% efficacious when given at 3, 4, and 6 months of age to 58,000 infants. In 1988-1989, the PRP-D vaccine was compared with the HbOC vaccine (oligosaccharide conjugated to CRM197 protein). Follow-up is continuing, but both vaccines seem to be efficacious after two doses in infancy.

Epidemiology of invasive Haemophilus influenzae type b disease

Invasive disease caused by Haemophilus influenzae type b (Hib) is typically a disease of young children, starting when the protection afforded by maternal antibodies is exhausted and ending when the child's own antibody production to the Hib capsular polysaccharide begins efficiently. There are, however, large variations between population groups in the incidence of the disease and the age at which it appears. Potential factors behind this variation include virulence genes of the bacteria and genetic susceptibility genes of the host. Although such genes and their effects can be identified, their impact on the disease's incidence is only minor. Potentially much more important appear to be socioeconomic factors that to a large extent determine the exposure of the child to Hib and to other infectious agents that may enhance both colonization and invasive infection by Hib.