Jinagsu Province is one of the provinces with high incidence of poliomyelitis historically. Eradication of poliomyelitis in the province had experienced five stages as follows: (1) Stage before administration of oral polio vaccines (OPV) (1956～1960); (2) Beginning of OPV administration (1961～1969); (3) Extensive administration of OPV (1970～1978); (4) Implementation of expanded program on immunization (EPI) (1979～1989) and (5)Eradication of poliomyelitis (1990～1999). While reviewing the adopted strategies in the process of polio eradication, two points should be emphasized: (1) To raise the OPV immunization coverage rate unceasingly. After carrying out in Jiangsu Province the EPI, we have taken steps to strengthen the construction of cold chain and to standardize the vaccination in clinics, thus to ensure the vaccination quatity. Based on routine polio vaccination, still we carried out supplementary vaccination to establish an effective immune barrier among the population; (2) To strengthen the AFP surveillance. The AFP surveillance system had been established in 1991 in Jiangsu Province, the various surveillance indexes now has reached every requirements for proving no polio virus exists. In the course of surveillance, we pursued a case-reporting encouragement system and an active AFP searching at regular intervals to strengthen AFP case reporting and surveillance. Since 1993, there was no wild-type polio virus found. To summarize and evaluate the strategies for poliomyelitis eradication not only can consolidate the achievements of the work but also can provide reference in controlling other viral diseases.

Using RT-PCR, we can detect measles virus hemagglutinin gene (H gene) of 635bp length directly from measles vaccine strain Shanghai-191, Edmonston strain, nasopharyngeal aspirates and throat swabs of the measles patients. The primers of RT-PCR based on H gene sequence of measles virus did not give the same products from rubella virus and influenza viruses (A1, A3, B). By second PCR amplification, the minimum quantity of measles virus required to give a positive signal was<0.01TCID50. Since the IgM antibody positive rate in early stage of measles patients is always low, the specificity and sensitivity of RT-PCR method may help diagnosing measles cases.

We analyzed the surveillance data of measles from January 1999 to October 2000 in Jiangxi Province for the aim of measles control. The results showed that 3*!184 measles cases were reported from the province and 1 reported case died. Most of the reported measles cases were under 15 years old. The incidence of measles in age group between 7-10 years old was higher than that in other age groups and most of the reported cases having vaccination histroy were 4-10 year old children. Both the sporadic and epidemic measles in some districts existed at the same time and the reported measles cases extensively distributed in all districts of Jiangxi Province. The outbreaks of measles in some districts had affected the morbidity of measles of the whole province To prevent and control measles outbreak are the main effective measures to control this disease.

Measles surveillance in Jiangsu Province started in 1999 by dividing the province into two sorts of areas. The first sort of area is economic well-developed area where EPI is carried out well and measles incidence is lower. The cities of this area investigated included Suzhou, Wuxi, Changzhou and Zhenjiang. The second sort of area included 9 cities (Nanjing, Xuzhou, Liangyungang, Nantong, Huaiyin, Suqian, Yangcheng, Yangzhou and Taizhou) where all the conditions are not as good as that mentioned in the first sort of area. The surveillance system of the province reported in 1999 a total of 938 suspected measles cases in 13 cities, of which 684 were confirmed as measles. The notifiable reporting system reported 846 suspected measles cases and 684 cases were confirmed. This indicated that the surveillance system operated well. The measles epidemiological features in two sorts of areas were compared. In first sort of area, including Nanjing, the measles cases of ≥15 years old accounted for 66.3% of the total cases. In second sort of area, not including Nanjing, the measles cases of <15 years old accounted for 90.8% of the total cases, and 73.2% of them were patients <10 years old. In 1999, there were 10 measles outbreaks occurred in the province and 218 measles cases were reported which accounted for 31.7% of the confirmed measles cases reported by the provincial measles surveillance system. 9% the 10 outbreaks occurred in the second sort of area, the cases were preschool and primary school children. The results showed that progression of EPI work was uneven in two sorts of areas of Jiangsu Province.

In order to investigate the occurrence of chronic hepatitis B virus(HBV) infection in HB vaccine inoculated infants born to HBsAg positive mothers and its affecting factors and also to study the effect of combined use of HB immunoglobulin (HBIG) and HB vaccine on the blocking of perinatal transmission of HBV, we divided 624 infants born to HBsAg positive mothers into two groups randomly. The first group of infants were simply vaccinated with HB vaccine 20μg at,0, 1, 6 months old. The second group of infants were inoculated with HBIG 100 IU at their birth and further vaccinated with HB vaccine 20μg at 1,2,7 months old. The HBsAg of the two groups of infants was tested at the age of 1,3,6,12,18,24 months old and every year by EIA. They were all followed up for 6.34±1.71 years averagely. The follow-up results showed that there were 89 childeren infected chronically by HBV, among them 82% appeared to be HBsAg positive, firstly seen before the age of 6 months mainly attributing to uterus infection. The HBV chronic infection rate of infants born to HBsAg, HBeAg positive mothers (HB vaccine immunized, 24.5%; HBIG+HB vaccine, 10.6%, P<0.005) was higher than that of infants born to HBsAg positive mothers (HB vaccine immunized, 10.7%; HBIG+HB vaccine 3.8%, P<0.025). Moreover, the chronicity rate of the infants whose HBsAg firstly appeared within 6　　months and were born to HBsAg, HBeAg positive mothers was higher than that of the infants born to HBsAg positive months (68%,40% respertively in HB vaccine inoculated group, P<0.025). Infants immunized combinely with HBIG and HB vaccine had their chronic HBV infection decreased from 17.6% to 5.0% at l year old as compared with that of HB vaccine inoculated infants. The total chronic HBV infection rate in children born to HBsAg, HBeAg positive mothers decreased from 24.5% to 10.6% (P<0.005) and that in children born to HBsAg positive mothers decreased from 10.7% to 3.8% (P<0.025). The HBV chronicity rate of HBsAg positive infants born to HBsAg, HBeAg positive mothers also decreased and that of infants born with HBsAg negative, but became positive after 1-6 months decreased from 40.9% to 0% (P=0.0315). The HBsAg seronegative conversion rate in l month old infants born to HBsAg positive mothers increased from 26.4% to 58.8% (P<0.025). All these data indicated that infants born to HBsAg positive mothers, though had been HB vaccine immunized, still had chronic infection, that was chiefly due to chronic uterus infection by HBV. The single use of HB vaccine can not completely block the uterus infection of HBV, but when combinatively used with HBIG, the blocking effect is more efficient, the chronicity of HBV infection also can be avoided.

This paper was to observe the revaccination effect of domestic yeast-derived recombinant hepatitis B vaccine (YRHBV) to children who were born to HBsAg and HBeAg negative mothers and had been immunized with full course of blood-derived hepatitis B vaccine 4 years ago at their birth. The treated group was revaccinated with 5μg YRHBV while the control group with 10μg blood-derived HB vaccine, their anti-HBs response was determined 1,12,24 months after revaccination. The results showed that a nice anti-HBs response was discovered in group A childeren, no matter how about the anti-HBs level before revaccination was. The kinetics of anti-HBs after YDHBV revaccination was similar to that of the blood-derived HB vaccine, no statistical difference was found. So, 5μg of domestic yeast-derived recombinant HB vaccine gave same immune effect as well as 10μg blood-derived HB vaccine.

Four kinds of indexes were selected to build up the routine immunization quality evaluating system. The indexes were the estimated immunization coverage rate, timely reporting rate of routine immunization report forms, incidence level of diseases related to EPI, and the external factors influencing routine immunization. By using deducing mark method, we evaluated the synthetic routine immunization quality on city and county level in Hubei Province. This evaluating index system and method have the characteristics of easy to perform, credibility, reasonableness and can be applied widely.

Chickenpox is an acute and highly infectious respiratory disease commonly seen in children.Varicela－zoster often results from the activation of latent virus in chickenpox called varicella－zoster virus（VZV）or called human herpesvirus type 3. Primary infection of VZV may induce typical disease of various severity and most healthy children infected with VZV have mild symptoms and good prognosis.But VZV infection，if occurs in special population such as persons of immune inhibition treatment will induce serious consequence or even death and it is as same serious as in adults.A detailed illustration of molecular biology，epidemiology，laboratory diagnosis，treatment and preventive strategy of the VZV were given.

Haemophilus influenzae (Hi) is a pathogen exclusively found in humans. It causes a wide range of infections from the upper respiratory tract to serious invasive diseases. Such as pneumonia, septicemia and meningitis. Strains of Hi are usually classif ied into six serotypes a to f and nontypeable H. influenzae (NTHI) according to the antigenicities and compositions of their polysaccharide capsules. Hib was a common cause of serious infections in younger children. The polysaccharide-protein conjugate vaccines against Hib had almost eliminated H. influenzae as a cause of pediatric meningitis. However, NTHI remains an important pathogen, particularly in children and the elderly. Efforts to understand and control NTHI disease have been hampered by the diversity of these bacteria. This review introduced the study progress about pathogenic mechanism of NTHI. In order to provide the help for development of vaccine, clinic treatment and prevent the occurrence of diseases causing by NTHI.

Virus-like particles (VLPs) structurally mimic the authentic virus whereas contain no viral genome. VLPs technique plays an important role in basic research such as virus assembly and virus morphology diversity. With special immunology properties, VLPs vaccine can induce immune response effectively. VLPs can act as adjuvant by regulating dendritic cells. Other adjuvant or polypeptide can be integrated into VLPs to construct chimeric vaccines. With the capability of packaging nucleic acid or other small molecules, VLPs can be used for vehicles to deliver these substances under suitable conditions. VLPs can substitute natural virus in immunology assay.