Windows 7 Security Essentials will continue to receive updates after January 14

Two weeks from now, Microsoft's Windows 7 operating system will no longer be supported. The main implication here is that users of this aging operating system will cease to receive security updates from Microsoft.

However, there was some confusion about whether users of Microsoft's Security Essentials (MSE) tool for Windows 7 would continue to receive anti-virus updates. Microsoft confirmed on its forums that MSE will continue to receive signature updates after January 14, 2020, the end-of-life date of Windows 7. However, the MSE platform will no longer be updated.

As pointed out by Bleeping Computers, it's still better to upgrade to Windows 10 as soon as possible:

Without a subscription to Windows 7 extended security updates, using the unsupported operating system will open users to vulnerabilities that will no longer be fixed. Furthermore, it is not uncommon for vulnerabilities or bypass methods to be discovered in antivirus software.

Therefore, even if you are willing to risk being affected by new vulnerabilities in Windows 7, it is still possible that malware distributors will come up with methods that bypass detections in Microsoft Security Essentials.