COST EFFECTIVENESS STUDY OF HIB
VACCINATION FOR CHILDREN
BELOW 5
YEARS IN JORDAN

*Pediatrician, Member of the Medical Committee of Jordanian Meningitis Foundation (JMF) , Amman- Jordan.

Invasive HIB-disease is a major cause of health problem in developed and developing countries, and where the HIB-vaccine was introduced within the routine immunization of infants and children, the incidence of the disease declined significantly.

This study is conducted to estimate the incidence of HIB Meningitis and HIB-Pneumonia in Jordan and its cost, revealing an incidence of HIB — Meningitis ranging between 20 - 30/100.000 children <5 years and HIB-Pneumonia of 75/100.000 children <5 years. Evaluating the benefit and cost effectiveness which can be obtained if the HIB vaccine was included within the EPJ of Jordan, we found that it is profitable to introduce the anti HIB-vaccine within the routine schedule of immunization of infants and children at risk to develop the disease as soon as possible.

The review of several published papers, articles and researches reporting unequivocal data and conclusion about the effectiveness and safety of the conjugate HIB vaccines when introduced in routine immunization schedule of small infants at the age of 2, 4, 6 and Booster dose at the age of 15 months, resulting in dramatic decrease in the incidence of meningitis and all invasive types of HIB disease to less than 1/100.000 of children <5 years old within ito 4 years of introduction of routine infant immunization. In several countries using the vaccine for longer periods of time and which have achieved relatively high coverage rates, the disease no longer occurs at all. The ability of the vaccine to eliminate disease is due to elimination of oropharyngeal carriage of the bacteria in well immunized populations, leading to absence of exposure to the bacteria even in un immunized children. The recent studies demonstrate that HIB conjugate vaccines are as efficacious in developing countries populations as they were in efficacy trials in the industrialized world. In addition the studies showed that the vaccine reduced all chest X-Ray documented pneumonia by more than 20%.

Reviewing all available data about the HIB Meningitis and all HIB invasive disease in several countries of the area like Syria, Kuwait, Qater and others we found an incidence > 20/100.000 children <5 years. Same incidence is recorded when we reviewed data registered in the Department of disease control in the Ministry of Health of Jordan in the “ Master file of obligatory notification Diseases Model”, Looking specifically after Bacterial Meningitis, (HIB meningitis, meningococcal meningitis, puenmococcal Meningitis) and others with negative results related to the demonstration of presence of Bacteria in CSF, which is in part due to high percentage of partial treated meningitis and inefficient laboratory tests.

In different studies done during the 90's in two main hospitals in Jordan with specialized and terminal pediatric services, the incidence rate of HIB meningitis per year ranged between 21~30/100.000(18) (19), and the mortality percentage reported is between 8-13%. Sequelaes detected in 21- 32% of survivors.

Also we took to consideration the cost of treatment of diagnosed cases during hospitalization, care of acute phase , prophylaxis and obligatory follow up of close contacts in addition to the cost of care required by diseased patients sequelaes, the fact of emotional, familial and social serious disturbances in addition to the material and emotional.

Deaths can be avoided by administering the vaccine for highly risk groups of infants and children < 5 years old >.

In addition to Meningitis, there is great interest in addressing the problem of Bacterial pneumonia, recognized in developing country as a major cause of morbidity, mortality and a common cause of admission for intrahospital treatment. To estimate the annual mortality and morbidity rates of pneumonia due to HIB in Jordan we applied the formula recommended by the Global program for vaccines and immunization established by the WHO in the “Generic Protocol for Population — based surveillance of Haemophilus influenza type B (1996)”.

Data from studies on the impact of HIB vaccine on the incidence of invasive disease after three doses was 95%, and for prevention of HIB pneumonia after two to three doses was 100%reducing the total incidence of pneumonia of different causes in 20%, this results coincide with several data and studies suggesting that 20% of total cases of pneumonia are caused by haemophilus influenza type B(13) . 

The center for disease control and prevention (Atlanta, GA, USA) and the WHO program for control of acute Respiratory infection (Geneva, Switzerland) recently reviewed the epidemiology and etiology of pneumonia in developing countries of the estimated 3.7 million acute lower respiratory tract infection

(ALRI ) deaths among children <5 years old in the developing world the CDC/ WHO review estimates that 342.000 (9%) are due to HiB(16) . This estimate of HIB ALRI deaths is approximately ten times more than that estimated number of HIB meningitis deaths among children < 5 years old in developing countries.

After reviewing the last annual statistical report of the MOH of Jordan (1998), there was no available information or data about deaths due to HiB-pneumonia, So applied the garenne at al formula .

Wich is recommended by WHO when there is no specific available information about mortality due to acute lower respiratory infection (ALRI), (2) resulted in at least 4.5 deaths /100.000 children <5 years and a total of at least 34 deaths per year from this age group.

HIB — pneumonia cases found to be at least equal to 75 cases/ 100.000 children <5 years and a total of at least 525 cases of HIB-pneumonia per years of this age group with percentage of HIB- Pneumonia mortality equal to 6.5% of the total number of children and infant with established HIB- Pneumonia . The previous results calculated up on crude death rate (per 1000 population) because no available data on mortality rate per 1000 children < 5 years, inspite of that ,those results provided us with a very useful data to calculate the minimal total cost of the two main groups of i-JiB disease( HiB-Meningitis, HIB- pneumonia) in children < 5 years.

Considering the lowest expected incidence of the disease and lowest percentage of mortality and morbidity we obtained the following results:

1.The cost of hospitalization and care of acute phase of HIB—Meningitis per year is equal to 99.400 JD.

2.Sequelaes care cost increasing yearly by the amount of 72.000 JD in accumulative manner.

3.Cost of prophylaxis provided to close contacts persons is equal to 14.200 JD per year.

4.Cost of total Deaths due to meningitis per year is equal to 369.200 JD

5.Cost of HIB-pneumonia which need 3 weeks of antibiotics treatment at least is equal to 551.250 JD per year.

6. Cost of HIB- Pneumonia deaths per year is equal to 1.105.000 JD

The total cost of HIB — Meningitis and HIB-pneumonia without calculation of the cost of other forms of HIB — invasive disease will be at least equal to 2.211.050 JD per year.

The cost of one dose of HIB —vaccine is equal or less than 2USD if covered by Public Health Services. Knowing that the total need per year is around 600.000 doses, the maximum total cost of vaccines needed per year will be around 1.200.000 USD (600.000 x 2 = 1.200.000) Equivalent to N 846.000 JD to protect all risk group <5years annually.

Considering the data collected from the master file of obligatory Notification Disease Model of the MOH of Jordan 1999/2000, reported Number of HIB Meningitis cases from the area of Hai — Nazzal where the pilot project of HIB vaccine Promoted by JMF and MOH which started one year ago ( Jun 99), Covered all infants and children <3 years and extended during the last month ( May 2000) to new areas of primary Health area of Amman, the safety efficacy, high protective rate and lower cost meaning of the introduction of  vaccine in the routine Immunization program of Jordan would be profitable, taking into account the economic point of view, eniotional, family and social serious disturbances due to Hospitalization, sequalaes and deaths caused by this disease which would he avoided and is perfectly preventable if the vaccine is Introduced in the schedule of Jordanian National program of Immunization.

CONCLUSIONS AND RECOMMENDATIONS:

Invasive HIB-disease is an important cause of Morbidity, Modality and disabilities, affecting mainly infants and child's <5years old, occurring with considerably important incidence in Jordan approximately equal to other developing countries.

The high incidence rate reported in developed countries before the era of HIB-Vaccine, declined dramatically after the introduction of HIB vaccine in the schedule of Routine immunization of infants and children to less than 1/100.000 children < 5years and the new cases presented later on were only in infants and children not immunized or not fully immunized for several reasons.

The introduction of HIB-vaccine results in life saving, disabilities prevention and materiaI cost reduction.

The introduction of HIB — vaccine in routine immunization in Jordan is advisable, because it will be of great benefit to decrease the incidence of HIB-disease cases and its cost significantly. Therefore We recommend the introduction of HIB — vaccine in the Expanded Program of Immunization (EPI) of Jordan applying the schedule recommended by the WHO for Anti-HiB vaccination.