[The 2009 H1N1 flu pandemic in Navarre, Spain]

BACKGROUND

To describe flu activity during the 2009-2010 pandemic in Navarre and compare it to previous seasons.

METHODS

An analysis was made of all flu cases reported in primary care and all the virological confirmations made in patients in primary care and in hospitals of Navarre between week 21 of 2009 and week 20 of 2010.

RESULTS

Influenza A (H1N1) Virus 2009 was detected in Navarre between week 23 of 2009 and week 2 of 2010, a period when 39 medically diagnosed cases of flu syndrome per 1,000 inhabitants were registered. The epidemic threshold was surpassed in two periods, with a peak in July and a greater one in November. The greatest incidence was reached in children aged between 5 and 14 years (121 per thousand), followed by the group of under fives. There were 224 hospitalisations (36 per 100,000 inhabitants) with confirmation of Influenza A (H1N1) Virus 2009, 8% of whom required admission to intensive care units and there were four deaths (0.6 per 100,000 inhabitants). The rate of hospitalisation was greater amongst children under five (163 per 100,000 inhabitants), while the probability of referral to intensive care increased with age.

CONCLUSION

In spite of not having a specific vaccine available until the season was very well advanced, Influenza A (H1N1)Virus 2009 produced a flu wave with similar levels to those of other seasons and its repercussion in hospitalisations and serious cases was moderate.

[Intermittent hematuria. Vesical schistosomosis. Concerning one case]

We present a clinical case of vesical schistosomiasis that we consider unusual in our environment. The clinical features of this parasitosis include an intermittent hematuria of several weeks evolution which is not resolved with the usual treatment. Due to the increase in the immigrant population arriving from endemic areas, we must pay greater attention to this emergent pathology. The process is resolved satisfactorily with treatment and complications are avoided.

[Hepatitis A seroprevalence in Navarra]

BACKGROUND

Determine the hepatitis A seroprevalence in Navarra. Because of the improvement in the hygienic-sanitary conditions, we hope to find a decline of the total prevalence.

METHODS

Population and random sample of Navarra, obtained by stratified sampling with proportional allocation of sex, age, and area of health care: 1,440 individuals over 15 years of age. Detection of total antibodies by enzyme immunoassay of microparticles.

RESULTS

Global seroprevalence: 79.24%. By age: 9.09% (16-19 years), 35.32% (20-29 years), 77.78% (30-39 years), 97.31% (40-49 years), 98.58% (50-59 years), 97.51% (60-69 years), 99.33% (70-79 years) and 100% (>79 years). By gender: 78.76% in men and 79.7% in women. Rural area 82.04% and urban area 75.77%. Areas of health care: Tafalla, 89.06%; Estella, 87.91%; Tudela, 82.88%; northern, 77.22%; Pamplona, 75.05%, and eastern, 70.97%.

CONCLUSIONS

The global prevalence is 79.24% and increasing progressively with the age. Greater seroprevalence in rural areas and in people in contact with livestock. Characteristics of the persons with seroprevalence for HAV in Navarra: inhabitant of the average area, of rural area, with average age and in contact with livestock.

[Trichinellosis: study of 2 outbreaks in Navarre]

BACKGROUND

We present two outbreaks of trichinosis occurred in the last two years in Navarre.

METHODS

After the detection of the initial case, an epidemiological study of all people presumably infected was carried out. We used the latex agglutination and ELISA tests to detect specific antibodies. We studied the characteristics of the infested meat, as well as the clinical symptoms, eosinophil counts and serologic status of the subjects. After three and twelve months those items were again monitored.

RESULTS

71 subjects who had ingested the infected meat were detected. Of them, 67 (94.3%) were enrolled in the study, 34 being involved in the first outbreak and 33 in the second. 15 (22.5%) of the 67 cases had symptoms suggestive of trichinosis, 30 (44.7%) had hypereosinophilia, and 25 (38%) had positive serologic test results. 25 subjects (38%) were diagnosed as having trichinosis. Two groups were made according to the characteristics of the meat consumed: 34 subjects (50.7%) had ingested thoroughly cooked meat (group A), whereas 33 (49%) had ingested poorly cooked meat (group B). After three months, only 5 patients were symptomatic and 10 had a high eosinophil count. After 12 months, all subjects were asymptomatic, had normal eosinophil counts and negative serologies.

CONCLUSIONS

1) An epidemiological survey and serologic determinations for trichina should be carried out when studying hypereosinophilia. 2) It is important to insist on the necessity of veterinary inspection of home-made pork products. 3) The ingestion of poorly cooked pork products increases the risk of Trichinella infection.

[Hepatitis B vaccination: immunogenicity of the plasmatic vaccine in hospital personnel]

The results and incidences of a hepatitis B vaccination program were evaluated in 310 health professionals from a general hospital constituting 26.8% of the whole staff. They were 102 males and 208 females which, on the basis of previous criteria, were inoculated with plasmatic vaccine (MSD) in the deltoid muscle. In only 299 (100 males and 199 females), post vaccination control laboratory studies were available. The overall antiHBs seroconversion rate was 95%; it was 92% in males and 96% in females, without significant differences (p greater than 0.05). The age group below 30 years had a better response (97%) than the 30-49 years group (95%), and this, in its turn, better than that over 50 years (90%), but the differences between groups were not significant (p greater than 0.05). The immune response was satisfactory (greater than 100 mUI/ml) in 85% of the study group, and in only 5% it was negative or scarcely measurable. The application of a fourth vaccine dose to nonresponders had variable results. In 20% of the vaccinated individuals adverse reactions were noted, more frequently after the first vaccine dose. We wish to emphasize that a vaccination program such as this demands a great planning, organization and follow-up effort to achieve success and cost-effectiveness. Importantly, it should be avoided that vaccination create a feeling of false security among health professionals inducing them to neglect other protective measures.

Seroepidemiology of the poliovirus in Monrovia (Liberia)

Neutralizing antibodies against poliovirus have been studied in 265 persons in Monrovia (Liberia). 34% of the individuals studied possessed antibodies against the three polioviruses, 23% against two, 26% against one; the remaining 17% showed none. The three poliovirus antibodies were evenly distributed amongst the population, although there was an indication that antibodies to polio 2 occurred more commonly in females than in males. The distribution of the antibodies did not seem to be influenced by place of residence, source of drinking water or social class. Significant variations in the immunological state according to age were noted. The study of concordance and discordance of antibody titre in the blood of neonates and their mothers revealed that the lower percentage of titre concordance for polio 3 has no statistical value. The low titre in the neonates (an average for each poliovirus scarcely above 1:16) is a sign of insufficient titre in the adults. The need for a massive antipoliomyelitis campaign among infants and adult women is stressed.