[1] In mid-May 2021, the Waikato District Health Board's hospital computer systems and phone lines were affected by a ransomware attack.

[2] On 25 May, an unidentified group claimed responsibility for the hack and issued an ultimatum to the Waikato DHB, having obtained sensitive data about patients, staff and finances.

[3] Hackers later dumped confidential medical, financial and patients' data onto the dark web, forcing the DHB to work with cyber-experts to minimise any potential privacy disclosures.

[5][3] By mid-June 2021, the Waikato DHB had managed to restore most health services and operations but faced a backlog of outpatient appointments due to the disruption caused by the ransomware attack.

[8] The area covered by the Waikato District Health Board is defined in Schedule 1 of the New Zealand Public Health and Disability Act 2000 and based on territorial authority and ward boundaries as constituted as at 1 January 2001.