Treatment
As with other Flavivirus infections, no cure is known for yellow fever. Hospitalization is advisable and intensive care may be necessary because of rapid deterioration in some cases. Certain acute treatment methods lack efficacy: passive immunization after the emergence of symptoms is probably without effect; ribavirin and other antiviral drugs, as well as treatment with interferons, are ineffective in yellow fever patients. Symptomatic treatment includes rehydration and pain relief with drugs such as paracetamol (acetaminophen). Acetylsalicylic acid (aspirin). However, aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) are often avoided because of an increased risk of gastrointestinal bleeding due to their anticoagulant effects. Epidemiology
Yellow fever is common in tropical and subtropical areas of South America and Africa. Worldwide, about 600 million people live in endemic areas. The WHO estimates 200,000 cases of yellow fever worldwide each year. About 15% of people infected with yellow fever progress to a severe form of the illness, and up to half of those will die, as there is no cure for yellow fever. Africa
An estimated 90% of yellow fever infections occur on the African continent. In 2016, a large outbreak originated in Angola and spread to neighboring countries before being contained by a massive vaccination campaign.
Vocal fold bowing, decreased vocal fold mobility, especially decreased mobility of the arytenoid cartilage, are often observed in vocal fold paresis. Glottal insufficiency is another common symptom observed in vocal fold paresis. In this case, the vocal folds do not come together properly. Glottal insufficiency may be hard to identify, especially when the area above the vocal folds is hyperfunctional. Hyperfunction may also make it difficult to detect the presence of vocal fold paresis. Hyperfunction of the area above the vocal folds may be considered a sign of glottal insufficiency and potentially, vocal fold paresis.In some cases, glottal closure may appear to be normal, however, asymmetries in the vocal folds may still be present. Though voice qualities may appear normal in some cases of vocal fold paresis or paralysis, mild differences in tension between the two vocal folds of the larynx can result in changes of voice pitch, intensity and reduced vocal stamina.Patients with either vocal fold paresis or paralysis may exhibit a breathy voice quality. This voice quality results from the increased activity of the vocal folds to compensate for the immobility of the PCA muscle(s). Patients may need to use more effort than normal when speaking and may find that their voice quiets or grows tired after speaking for a long time. This is known as vocal fatigue. Patients may also complain about having a limited pitch range and trouble varying their pitch at quick rate.