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Invasive 'yellow fever' mosquito newly found in Castro Valley
Summary by The San Francisco Editorial Desk · Based on reporting by Gillian Mohney , SFGate - Bay Area News
· July 23, 2026
· 1 min read
A "perfect combination" of hot and humid weather can help mosquitoes flourish.
Story provenance No corrections
Summary created by The San Francisco Editorial Desk — automated, rule-governed Original reporting Gillian Mohney, SFGate - Bay Area News Original story Read at the source Source published Jul 23, 2026 Indexed here Jul 23, 2026 AI assistance Automated summary drawn from the source’s own published text Prepublication human review No — editorial rules, flagged-item review, and published samples
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Key takeaway The mosquito species in question is referred to as the "yellow fever" mosquito.
Invasive mosquitoes have been found in the Bay Area, specifically in Castro Valley. The mosquito species in question is referred to as the "yellow fever" mosquito.
A certain type of weather can contribute to the flourishing of mosquitoes. This weather is described as a "perfect combination" of hot and humid conditions.
Further details about the discovery of the invasive mosquitoes are available from SFGate, a source for Bay Area news.
Why this matters
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About this story
Original reporting by SFGate - Bay Area News . The San Francisco surfaces reporting from trusted publishers and adds local editorial context so readers can quickly understand what a story means for their community. We attribute every source, link to the original report, and follow a documented editorial standards policy. To understand how stories are selected and reviewed, read our about page .
For the complete original report, visit SFGate - Bay Area News . Have a tip or correction? Contact our newsroom .
Category: local ·
Published: July 23, 2026 ·
Source: SFGate - Bay Area News ·
Reading time: 1 min
Frequently asked about this story
What is this story about? A "perfect combination" of hot and humid weather can help mosquitoes flourish.
When was this published? This article was first published on July 23, 2026 by SFGate - Bay Area News and curated for The San Francisco readers.
Who reported this story? This story was reported by Gillian Mohney at SFGate - Bay Area News. To learn more about how The San Francisco selects and reviews stories, see our editorial standards .
Where can I find related coverage? See more local coverage from The San Francisco, or browse our daily briefing and topic hubs .
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