MORGAN STANLEY: These 7 pharma companies will be critical to fighting infectious diseases brought on by climate change

Like Sanofi, GlaxoSmithKline already has been developing drugs to treat major tropical diseases and the large-scale manufacturing capabilities necessary.

Moderna uses its smaller size to its advantage, according to the note. The emerging company has a faster development process and has demonstrated a potential pipeline for drugs combatting Zika and chikungunya.

Takeda plans to launch a vaccine in 2020 that protects against four strains of the dengue virus.

Merck has several vaccines in development, including treatments for Ebola and the dengue virus.

Janssen has a long relationship with the Biomedical Advanced Research & Development Authority and has successfully developed vaccines for Ebola. The company also has large-scale manufacturing capabilities for its treatments, but doesn't currently have much of a research pipeline related to the key tropical diseases mentioned in the note.

Pfizer doesn't appear to have any tropical disease vaccines in development but has the resources to start such a pipeline, according to Morgan Stanley. The company is the largest in the pharmaceutical sector by market cap.