Analysis of the yearly transition function in measles disease modeling.

Globally, there were an estimated 9.8 million measles cases and 207 500 measles deaths in 2019. As the effort to eliminate measles around the world continues, modeling remains a valuable tool for public health decision-makers and program implementers. This study presents a novel approach to the use of a yearly transition function that formulates mathematically the vaccine schedules for different age groups while accounting for the effects of the age of vaccination, the timing of vaccination, and disease seasonality on the yearly number of measles cases in a country. The methodology presented adds to an existing modeling framework and expands its analysis, making its utilization more adjustable for the user and contributing to its conceptual clarity. This article also adjusts for the temporal interaction between vaccination and exposure to disease, applying adjustments to estimated yearly counts of cases and the number of vaccines administered that increase population immunity. These new model features provide the ability to forecast and compare the effects of different vaccination timing scenarios and seasonality of transmission on the expected disease incidence. Although the work presented is applied to the example of measles, it has potential relevance to modeling other vaccine-preventable diseases.

[A comparative study of thio-tepa and mitomycin C in the treatment of pterygium. Preliminary results]. / Etude comparative du Thio-tepa et de la Mitomycine C dans le traitement du ptérygion. Résultats préliminaires.

AIMS: To compare the efficacy of Thio-tepa and Mitomycine C to obviate recurrence; to compare cost-efficacy ratios; to evaluate their facility of use and their complications. METHODS: In a prospective blinded study, 36 patients undergoing surgery for 46 primary and recurrent pterygium were assigned randomly to three groups: group 1 received 0.02 mg/ml of Mitomycine C three times daily for 5 days; group 2 received Thio-tepa four times daily for 6 weeks, group 3 served as a control receiving distilled water three times daily for five days. RESULTS: Recurrence rates were 38%, in group 1; 28% in group 2; 82% in group 3 respectively. Follow-up ranged from 15 to 44 weeks (mean 27.93 +/- 8.9 weeks). Mean delay recurrence time was 6.3 weeks. Topical Mitomycin caused: iritis, conjunctival irritation, excessive lacrymation, photophobia, ocular pain; Thio-tepa caused: photophobia, foreign body sensation, headache. CONCLUSIONS: Mitomycine C appears to be an effective and safe adjunctive treatment for this cost-efficacy and this facility of use comparison.

[Renal cysts at Yaounde (Cameroon). Prevalence and echographic profile]. / Les kystes rénaux à Yaoundé (Cameroun). Prévalence et profil échographique.

Few studies have addressed the prevalence of renal cyst in African countries south of the Sahara, although this condition is highly prevalent in other parts of the world. To determine the prevalence and the clinical and sonographic features of renal cysts in a population of black africans, we reviewed 1,527 consecutive sonograms performed at the Yaoundé Teaching Hospital in Cameroon in patients aged 0 to 82 years. We found 47 patients harbouring at least one renal cyst (prevalence 3.08%). Prevalence of renal cyst increased with age, from 0% before the age of 20 to more than 10% after the age of 70. Most of the renal cysts found were solitary and caused no symptoms. Both sexes and both kidneys were equally affected. Diameter of the cyst exceeded one centimeter in most instances. Drainage under ultrasonographic control was performed in one case. Overall, in our institution in Yaoundé prevalence of solitary renal cyst was lower than in Western studies but clinical and sonographic patterns were consistent with previous data.

[Ophthalmologic manifestations of AIDS in an African milieu. Report of 45 cases]. / Manifestations ophtalmologiques du SIDA en milieu africain. A propos de 45 cas.

Acquired Immune Deficiency Syndrome (AIDS) is a pathological entity whose agent is a virus called HIV (Human Immunodeficiency Virus). The principal immunological deficit is the insufficience of immunity in mediation cell. Actually AIDS can be considered as the "bubonic plague" of the 20th century. Eye lesions caused by AIDS could present in 54 to 94% of patients of AIDS (3,19). Eye symptoms can be classified into four main categories or groups: retinal vascular lesions, eye opportunist infections, neoplasms of the eye surface and the orbit and finally neuro-ophthalmological anomalies. This study was realised at the university clinic of Mont Amba in Kinshasa, Zaire. A total of 45 cases were studied of which 42 cases with full blown AIDS (1 Congolese, 3 Ruandese, 1 Zambian and 37 Zaireans) and the other three were HIV positive (all were Zaireans). Among the 45 cases, 20 were studied retrospectively with a counting down of 5 years, and 25 others comprised of a prospective group of study or research. The patients were seen either in an ophthalmology Department/Service, or in a medical Service/Centre or in both. The criteria of diagnosis of AIDS were almost the same: skin anergy, infections and/or neoplasm opportunists, the lymphopenia T4, the report T4/T8 low or inversed and the HIV serology positive. A complete opthalmological test was undertaken, the indirect ophthalmoscopy and the retina fluorography were not done. A sex ratio is 1,64 (28 men for 17 women). The 45 patients were sexually active heterosexuals. None of them used drug intravenously. No accidental case of blood transfusion was revealed.(ABSTRACT TRUNCATED AT 250 WORDS)

[Strabismus and heterophoria: the situation in Zaire]. / Strabismes et hétérophories: la situation au Zaïre.

The results of a prospective study of 66 cases of squint among black Zaïrian people are presented. The frequency of strabismus in routine ophthalmic consultation was estimated at 1.5% with a large number of exodeviations (1.25%). Excessive divergence was by far the commonest form of exodeviations. A large pupillary distance and telorism are common in Zaïrian people.

[Retinoblastoma: 21-year review]. / Rétinoblastome: revue de 21 ans.

The natural history and prognosis of retinoblastoma were analysed using data from 73 medical records with diagnosis of retinoblastoma registered during 1963-1983 at University Hospital of Kinshasa (Zaïre). Of the 73 cases, 24 children (33%) were bilaterally affected. There were 38 (52%) boys and 35 (48%) girls. Ages at diagnosis ranged from 1/2 year to 6 years with an average age of 2.4 years. The white pupil was the most common initial sign. Many of our patients were severely affected with massive tumor filling the entire eye with vitreous seeding and poor general condition. Because of the more advanced stage of the tumor at time of diagnosis, surgery was the usual form of treatment. Only 5 children in our series showed a long-term survival, longer than 3 years after surgical treatment for retinoblastoma.

Common causes of blindness in Zaïre.

An analysis of 50 000 patients' medical records was made to determine the commonest causes of blindness in Zaïre. It was found that the commonest causes of blindness in order of frequency were glaucoma (31%), cataract (18.4%), optic atrophy (16.3%), onchocerciasis (4.9%), and corneal leucoma (4.9%).

[Causes of blindness in Zaire]. / Causes de la cécité au Zaïre.

From 50.000 patients treated at Eye Department of University Hospital of Kinshasa (Zaire), 944 or 19% were registered legal blind. The male-to-female ratio was 2/1 and 24% of legal blind were in the age group of 0-19 years corresponding to preschool and school period. Blindness incidence increased with advancing age. Glaucoma (31%) was by far the commonest cause of blindness in our sample and in all age groups. Cataract (18,4%) and optic atrophy (16,3%) respectively came in the second and the third position. Only cataract not treatable surgically was considered. Onchocerciasis (4,9%) appeared in the fourth position but this evaluation is a minimal one because Kinshasa is situated far away from some important endemic areas and villages. Onchocerciasis was absent among legally blind younger than 20 years, its importance increased with advancing age. Trachoma is unknown in Zaire and was absent from our list of blinding ocular diseases. Xerophthalmia and keratomalacia in its typical form was rarely a cause of blindness. The common blinding affections in developed countries such as, senile macular degeneration, hereditary chorioretinal dystrophies, diabetic retinopathy are poorly represented in our statistics. Some prophylactic and therapeutic suggestions are given: Persons with glaucoma are generally examined very late, and are difficult to be treated by either rigorous application of current miotics or surgical techniques for glaucoma. Pilocarpine with high concentration (4%, 6%) alone or associated to Timolol gives usually rather good tonometric results. Filtering operations for glaucoma (Elliot trepanation, trabeculectomy) can improve or stabilize the glaucoma but in some cases no improvement is noted.(ABSTRACT TRUNCATED AT 250 WORDS)