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Rubella is a systemic virus infection that is usually mild. It can, however, cause severe birth defects known as the congenital rubella syndrome (CRS) when infection occurs early in pregnancy. As many as 8%–13% of children with CRS developed autism during the rubella epidemic of the 1960s compared to the background rate of about 1 new case per 5000 children. Rubella infection and CRS are now rare in the U.S. and in Europe due to widespread vaccination. However, autism rates have risen dramatically in recent decades to about 3% of children today, with many cases appearing after a period of normal development (‘regressive autism’). Evidence is reviewed here suggesting that the signs and symptoms of rubella may be due to alterations in the hepatic metabolism of vitamin A (retinoids), precipitated by the acute phase of the infection. The infection causes mild liver dysfunction and the spillage of stored vitamin A compounds into the circulation, resulting in an endogenous form of hypervitaminosis A. Given that vitamin A is a known teratogen, it is suggested that rubella infection occurring in the early weeks of pregnancy causes CRS through maternal liver dysfunction and exposure of the developing fetus to excessive vitamin A. On this view, the multiple manifestations of CRS and associated autism represent endogenous forms of hypervitaminosis A. It is further proposed that regressive autism results primarily from post-natal influences of a liver-damaging nature and exposure to excess vitamin A, inducing CRS-like features as a function of vitamin A toxicity, but without the associated dysmorphogenesis. A number of environmental factors are discussed that may plausibly be candidates for this role, and suggestions are offered for testing the model. The model also suggests a number of measures that may be effective both in reducing the risk of fetal CRS in women who acquire rubella in their first trimester and in reversing or minimizing regressive autism among children in whom the diagnosis is suspected or confirmed.

An estimated 25%–32% of veterans of the 1991 Gulf War continue to experience multiple unexplained health problems known as Gulf War Illness (GWI). GWI encompasses chronic pain, musculoskeletal weakness, headache, fatigue, cognitive deficits, alterations in mood, and numerous multi-system complaints. Most potential exposures implicated in GWI were not well documented but included varying levels of several neurotoxicants as well as the anticholinergic drug pyridostigmine bromide (PB), which was routinely taken as prophylaxis against the nerve agent soman. While some veterans also took chloroquine as an antimalarial agent, the literature suggests an association between receipt of multiple vaccinations prior to or during the conflict (perhaps combined with other exposures), and GWI. In-theater exposures may account for any single individual veteran’s ill health but many veterans of the same era who were not deployed overseas also suffer the same or similar symptoms. The features of GWI also overlap with those of fibromyalgia, chronic fatigue syndrome and multiple chemical sensitivity, in all of which liver dysfunction has been documented, suggesting a unifying hypothesis. It is proposed that multiple vaccinations, with concurrent or subsequent exposure to PB or additional chemical insults of a liver-damaging nature, plausibly explain the pathogenesis and the observed chronicity of GWI. The suggested mechanism for GWI is thus a chemically-induced impaired liver function, with the spillage of stored vitamin A compounds (“retinoids”) into the circulation in toxic concentrations, resulting in an endogenous chronic form of hypervitaminosis A. Implications of the hypothesis are briefly reviewed.

The modern medical literature implicates malaria, and particularly the potentially fatal form of cerebral malaria, with a risk of neurocognitive impairment. Yet historically, even milder forms of malaria were associated in the literature with a broad range of psychiatric effects, including disorders of personality, mood, memory, attention, thought, and behaviour. In this article, the history of psychiatric effects attributed to malaria and post-malaria syndromes is reviewed, and insights from the historical practice of malariotherapy in contributing to understanding of these effects are considered. This review concludes with a discussion of the potentially confounding role of the adverse effects of anti-malarial drugs, particularly of the quinoline class, in the unique attribution of certain psychiatric effects to malaria, and of the need for a critical reevaluation of the literature in light of emerging evidence of the chronic nature of these adverse drug effects.

BackgroundMefloquine is commonly prescribed to prevent malaria in travellers, and has replaced other drugs because Plasmodium falciparum is commonly resistant to them. However, mefloquine may be associated with neuropsychiatric harmful effects.

Background: Mefloquine is a clinically important antimalaria drug, which is often not well tolerated. We critically reviewed 516 published case reports of mefloquine adverse effects, to clarify the phenomenology of the harms associated with mefloquine, and to make recommendations for safer prescribing.

A prospective randomized double-'blind' trial was undertaken during a military exercise in East Africa to determine whether there was a significant difference in the incidence of side effects experienced by soldiers taking mefloquine 250 mg weekly compared with those taking chloroquine 300 mg weekly and proguanil 200 mg daily as chemoprophylaxis for malaria. Subject to their informed voluntary consent, male soldiers who were not aviators were included in the study. Identical questionnaires were completed voluntarily at the end of 2 and 8 weeks. Symptoms were classified by nature into-'all', 'neuropsychological', 'enteric' and 'other', and by severity into 'severe' and 'very severe'. The proportions of respondents experiencing side effects were compared to seek statistically significant differences between the chemoprophylactic groups. Questionnaire 1 was completed after 2 weeks by 183 of 317 subjects (58%) randomly assigned mefloquine and by 176 of 307 subjects (57%) randomly assigned chloroquine-proguanil. The incidence of putative side effects was not significantly different between the groups (71/183 vs. 70/176), odds ratio 0.96 (95% confidence interval [CI] 0.63 to 1.47). Questionnaire 2 was completed after 8 weeks by 145 of 317 subjects (46%) randomly assigned mefloquine and by 142 of 307 subjects (46%) randomly assigned chloroquine-proguanil. The incidence of putative side effects was still not significantly different between the groups (95/145 vs. 103/142), odds ratio 0.72 (95% CI 0.43 to 1.19). None of the subjects developed a serious neuropsychological reaction. Among respondents, 12.8% and 38% admitted lack of full compliance at 2 and 8 weeks, respectively. Exclusion of these subjects during a secondary analysis did not affect the results. None of the subjects developed malaria in the 12 months following return to the UK. Subject to the limitations of a response rate that was smaller than desired and the fact that the study was conducted in fit male military personnel, these results support evidence which indicates that mefloquine is no more toxic than chloroquine-proguanil.