PURPOSE:To describe two cases of anterior and intermediate uveitis following yellow fever vaccination with fractional dose.

METHODS:Case report.

RESULTS:Case 1: A 35 year-old healthy woman presented with unilateral anterior uveitis 10 days after the yellow fever vaccination. Testing excluded infectious and rheumatic diseases and the episode was fully recovered after a short course of topical treatment. Case 2: A 21 year-old previously healthy woman presentedwith blurred vision in the left eye (OS) 14 days after the yellow fever vaccination. The ophthalmic examination of the OS revealed intermediated uveitis. Testing excluded infectious and neurological diseases. After six weeks of treatment with oral prednisone, the ocular inflammation had resolved.

CONCLUSION:Physicians should be aware of the possibility of eye inflammation following the yellow fever vaccination.

OBJECTIVE:To describe a case of infant meningoencephalitis that was probably caused by yellow fever vaccine virus transmitted via breastmilk.

DESCRIPTION:A 38-day old patient was admitted to hospital on May 23, 2009, with fever. On May 25, 2009, convulsive crises began. Cerebrospinal fluid (CSF) test results were suggestive of meningoencephalitis. The mother had been given a dose of yellow fever vaccine and the baby was on exclusive breastfeeding. The baby was discharged after the convulsive crises were controlled. Tests identified IgM antibodies specific for yellow fever in both serum and CSF.

COMMENTS:In 2009, the first case was confirmed of meningoencephalitis caused by the yellow fever vaccine virus transmitted via breastmilk. We describe a second case in which the vaccine virus was possibly the etiologic agent of meningoencephalitis. The Brazilian Ministry of Health now recommends delaying vaccination of nursing mothers until their children reach 6 months or providing them with guidance on alternative options to avoid the risk of transmission of the vaccine virus via breastmilk.

Narcolepsy with cataplexy is a rare, but important differential diagnosis for daytime sleepiness and atonic paroxysms in an adolescent. A recent increase in incidence in the pediatric age group probably linked to the use of the Pandemrix influenza vaccine in 2009, has increased awareness that different environmental factors can"trigger"narcolepsy with cataplexy in a genetically susceptible population. Here, we describe the case of a 13-year-old boy with narcolepsy following yellow fever vaccination. He carries the HLA DQB1*0602 haplotype strongly associated with narcolepsy and cataplexy. Polysomnography showed rapid sleep onset with rapid eye movement (REM) latency of 47 min, significant sleep fragmentation and a mean sleep latency of 1.6 min with sleep onset REM in four out of four nap periods. Together with the clinical history, these findings are diagnostic of narcolepsy type 1. The envelope protein E of the yellow fever vaccine strain 17D has significant amino acid sequence overlap with both hypocretin and the hypocretin receptor 2 receptors in protein regions that are predicted to act as epitopes for antibody production. These findings raise the question whether the yellow fever vaccine strain may, through a potential molecular mimicry mechanism, beanother infectious trigger for this neuro-immunological disorder.

BACKGROUND:Vaccinations are preventive measures against serious infections. In relation to the number of vaccinations per year, the incidence of severe complications is extremely low.

PATIENT:Two weeks after vaccinations against hepatitis A, hepatitis B and yellow fever in preparation for a trip to Africa a 21-year-old woman experienced an acute and irreversible loss of vision to 0,05 and nasal visual field defect in the left eye. Whereas vision acuity did not recover the scotoma disappeared within 6 weeks. Cerebrospinal fluid showed a lymphocytic pleocytosis. Oligoglonale bands were absent. Pathological parameters were not presented in the serum. The MRI showed a hyperintense thickening of optic nerve,as well as a hyperintense focus in right temporal side using the T(2)W-Sequence.

CONCLUSION:Only few cases have been reported with neurological complications, such as encephalitis, following vaccinations each of the above mentioned. As no other causes for the inflammation were found, the optic nerve involvement must have been caused by the vaccination. Which of the three vaccinations caused encephalitis can not be classified.

In April, 2009, the state health department of Rio Grande do Sul, Brazil, was notified by the Cachoeira do Sul municipal health department of a case of meningoencephalitis requiring hospitalization in an infant whose mother recently had received yellow fever vaccine during a postpartum visit. The Field Epidemiology Training Program of the Secretariat of Surveillance in Health of the Brazilian Ministry of Health assisted state and municipal health departments with an investigation. This report summarizes the results of that investigation, which determined that the infant acquired yellow fever vaccine virus through breast-feeding. The mother reported 2 days of headache, malaise, and low fever occurring 5 days after receipt of yellow fever vaccine. The infant, who was exclusively breast-fed, was hospitalized at age 23 days with seizures requiring continuous infusion of intravenous anticonvulsants. The infant received antimicrobial and antiviral treatment for meningoencephalitis. The presence of 17DD yellow fever virus was detected by reverse transcription--polymerase chain reaction (RT-PCR) in the infant's cerebrospinal fluid (CSF); yellow fever--specific immunoglobulin M (IgM) antibodies also were present in serum and CSF. The infant recovered completely, was discharged after 24 days of hospitalization, and has had normal neurodevelopment and growth through age 6 months. The findings in this report provide documentation that yellow fever vaccine virus can be transmitted via breast-feeding. Administration of yellow fever vaccine to breast-feeding women should be avoided except in situations where exposure to yellow fever viruses cannot be avoided or postponed.

OBJECTIVE:To assess a possible association between Yellow fever (YF) vaccine (inadvertently) administered during early pregnancy and spontaneous abortion.

METHOD:A hospital-based case-control study conducted in a Brazilian town after a YF vaccine campaign that followed an epidemic of dengue. The study included 39 women who attended a university hospital with spontaneous abortion (cases) and 74 pregnant women attending the antenatal clinic of that hospital (controls).

RESULTS:The crude odds ratio (relative risk estimate) of this association was 2.49, which dropped to 2.29 (95% CI 0.65-8.03) when adjusted for several confounders by multiple logistic regression. Dengue and exposure to organophosphate insecticide fogging during pregnancy were not associated with spontaneous abortion.

CONCLUSION:This study, although small and with low power, provides some evidence that women vaccinated with YF vaccine during early pregnancy have an increased risk of having spontaneous abortion. Based on these findings a sensible recommendation should be to avoid YF vaccination of pregnant women unless their risk of acquiring YF outweighs the risk of vaccine-related abortion.