Study on epidemiological characteristics of the Japanese Encephalitis in Ha Nam during 2001 - 2006

Background: Viet Nam is located in the epidemiological region of Japanese Encephalitis (JE). JE vaccine manufactured in Viet Nam has been used in the national vaccination program since 2003, but there has been no scientific study on the effectiveness of this program in Ha Nam province. Objectives: To investigate the epidemiology of JE and effectiveness of vaccinations in Ha Nam province from 2001-2006. Subjects and method: All residents in Ha Nam province, with the key focus group being JE cases. The retrospective and prospective epidemiological descriptive method was used. Results: The records of 148 cases of JE were collected. Among them, 42.5% (63 cases) were confirmed as JE by MAC-ELISA. The incidence and mortality rate were 1.29/100,000 and 0.12/100,000, respectively. Confirmed JE cases were found annually in all districts of Ha Nam province. However, it has been in decline, especially since the vaccination program was implemented for 1-5 year old children. The disease occurred in the summer with the peak in May and June (80.9% of total cases). Most of the cases were children under 15 years old (98.4%). The highest incidence rate was 6.4/100,000; 5.5/100,000 and 5.3/100,000 in the children aged 5-9, 1-4 and under 1 year old, respectively. Conclusion: The vaccination program appeared effective in reducing the mortality and morbidity of JE among children in Ha Nam province.

Status of neonatal tetanus (NT) after 10 years of elimination program implementation in the Northern region, 1992-2001

After 10 years of implementing the program of neonatal tetanus elimination from 1992 to 2001 in the Northern region, the tetanus toxoid coverage for pregnant and for child bearing age women have always been maintained at greater than 84%. The incidence of NT per 1000 live births has decreased, from 0.23 in 1994 to 0.07 in 2001. The disease has been eliminated at provincial level since 1995 and at district level since 1999.

Remarks on an outbreak of rubella in HaNoi

An outbreak of rubella occurred from 2nd March to 4th April, 2001, in three districts: Cau Giay, Tu Liem, Dong da of Ha Noi. There were 62 rubella cases aged from 1 to 25 years. Most of the cases were observed in age group 5-9 years (80,6%). The typical symptoms were fever (100%), rash (87,1%), itching (56,4%), coryza (35,5%). Serum samples from 9 cases were tested by MAC-ELISA, and all were positive.

Efficacy of prevention of Japanese encephalitis by injection of Japanese encephalitis vaccine produced by the National Institute of Epidemiology and Hygiene in Gia L­¬ng district, B¾c Ninh province during 1993-1999

The rate of Japanese encephalitis in Gia L­¬ng district was 21.4/100000, higher 4-5 times than other regions in the country. The disease occurred mainly in children under 15 years. After first 3 years (1993-1995) of injection, the rate of Japanese encephalitis was not reduced due to the rate of vaccination. However, because the rate of vaccination was increasingly during 1996-1999, the morbidity rate was gradually reduced from 21.4/100000 (in 1993) to 12.3/100.000 (in 1996) and 1.4/100.000 (in 1999). After 7 years of vaccination there was only one case received 2 injections of Japanese encephalitis vaccine suffered Japanese encephalitis among 109 total cases of Japanese encephalitis. The efficacy of vaccine of institute of epidemiology and hygiene was 99.3%.

Preliminary results of a study on antibody response to measles vaccine in children in Thanh Hoa province

The study included 890 children from 2 to 10 years of age in Thanh Hoa province. The seroconversion rate to measles vaccine increased from 61% to 83% after the booster dose of measles vaccine. Antibody mean titer significantly increased from 14.9+/-10 PANBIO units to 18.6+/-7.6 PANBIO units. The increase was high significant in negative sera. Antibody mean titer varied by districts. However, antibody response to measles vaccine signigicantly increased after the 2nd dose of measles vaccine in all the districs

Some remarks on diphtheria in VietNam, 1980-2001

The results of epidemiological surveillance showed that the incidence of diphtheria has reduced by 71% in the period of 1996 - 2001 compared with that in the period of 1991-1995, as a result of DPT immunization for children under 1 year of age in the EPI that has been accelerated since 1986. Especially, since 1994 the DPT immunization coverage has been sustained at greater than 90%. In the period of 1991-2002 the incidence of diphtheria was high in some provinces of the northern region. The disease occurred all year round, however, the incidences were highest in December and lowest in February, case mortality inhabitants rate recorded was 10.8%.

Achievement of poliomyelitis eradication

The results of the basic immunization of 3 doses of oral poliomyelitis vaccines for infant and boost immunization of 2 doses of oral poliomyelitis vaccine during 1993-1997 have shown that the poliomyelitis was significant reduced from 152 cases in 1993 to no case in 1998. The last case of poliomyelitis occurred in Phu yen province in 19th January 1997. In 2000, the poliomyelitis was eradicated in Vietnam. However, in order to prevent from returning the disease

Effectiveness of the polio eradication program in Viet Nam, 1993-1998

After 5 years, since 1993, the strategies for polio eradication have been well implemented. Coverage of routine immunization with 3 doses of OPV to children under 1 year of age has always been maintained higher than 90%. Coverage of supplementary immunization with 2 doses of OPV to children under 5 years of age during the NIDs has been achieved greater than 98%, surveillance of all the acute flaccid paralysis cases with collection of 2 adequate stool specimens for the identification of wild poliovirus. The results of the surveillance show that wild poliovirus cases have disappeared, decreasing from 152 cases in 1993 to 0 cases in 1998. The last cases of wild poliovirus identified in Phu Yen province of Central region had the date of onset on the 29th January 1997.

the complications of the ocular hypertension due to the chemical burn clinical and treatment

14 patients with the ocular burn/223 patients with burn in which male: 8, female: 6 children: 3 adult: 11, burn with the hypertention: 6.2%. The results have shown that. The results: the ocular burn should be immediately cleaned with NaCl 0.9% within 30 minutes, it is contraindicated for use of antagonist because of the more burn. The ocular hypertension found in the moderate and severe burns. It is difficult to evaluate. The treatment required the combination of theinternal treatment and surgical treatment. The diagnosis of the ocular hypertension due to burn helps the conservation of the eyeball, keeps a functional part from which the photo surgery such as the aritificial corneal transplantation can be applied.

Japanese encephalitis in Vietnam during 1991-2001

The Japanese encephalitis Circulated in Vietnam, especially in the delta provinces of Northern Vietnam. The yearly morbidity rate was 3-5 /100.000 rehabitants. The disease occurred mainly in ages of 1-15, highest in ages of 5-9 and followed by ages of 1-4 and in the summer (May, June, July). Vietnam manufactured the vaccine of encephalitis. It should strengthen the health communication and education and expanded immunization for susceptible ages

Japanese encephalitis control by Japanese encephalitis vaccine in Expanded Program of Immunization in Vietnam

The outcomes of vaccination in 1 to 5-year children were surveyed in high-risk districts between 1997 and 2001. The Japanese encephalitis vaccination schedule as follows: In the first years, the children receive 2 injections with 1-week interval, in the next year they receive the third injection. The injection dose is 0.5 ml subcutaneous. Results: For 5 years continuously, there were 1,472,608 one to five-year children had immunized, reached rate of 94.7% in 90 high-risk districts. The program produced dramatic effect on prevention. The incidence of Japanese encephalitis dropped gradually over years. By 2002, the cases reduced by one third in comparison with previous time

The immunization coverage of Japanese encephalitis vaccine produced by the NIHE in the EPI, Northern region, 1997-2000

For 4 consecutive years 1997-2000, immunization with Japanese encephalitis (JE) vaccine produced by the NIHE has been extended into the 90 high risk districts of the Northern region. 1.219.779 out of 1.296.248 children aged 1-5 years were immunized with two doses of JE vaccine, a total of 94.1% and 833.199 out of 878.643 children aged 1-5 years were also immunized with a booster dose achieving a coverage of 94.83%. There were no complications reported after JE immunization. Disease surveillance results in these districts showed that: the incidence of JE has decreased each year and from 1995 to 2000 the incidence was reduced 2.4 times.

Some remarks on cholera in Viet Nam, 1986-2000

The results of cholera surveillance from 1986-2000 showed that the incidence of the disease has dramatically decreased from 9.37 per 100.000 population in 1986 to 0.14 per 100.000 population in 2000. The disease has occurred all year round. However, the highest incidence was in January. February and the lowest incidence was in July, August. Cholera has mainly been recorded in provinces of central and Southern regions. Causative agent was Vibrio cholerae El Tor serotype Ogawa. The disease has spread through ingestion of seafood shrimp and fish sauces, water contaminated with Vibrio cholerae.

Current status of some vaccine preventable diseases in Vietnam, 1987-1998

Vietnam has implemented the Expanded Program on Immunization (EPI) since 1981. Since 1986 the EPI has been accelerated. From that time, the proportion of full immunization coverage has steadily increased every year. The EPI has significantly impacted on the downward trend of all vaccine preventable diseases. In parallel with an increase of full immunization coverage, the incidences of the EPI target diseases have decreased each year. Especially, poliomyelitis has dramatically decreased from 559 cases in 1992 to 0 case in 1998. Neonatal tetanus has been eliminated since 1995 by achieving a rate below 1 per 1000 live births at the provincial level. Diphtheria is no longer a problem of community health. Measles has fallen by 47% between 1987-1998.